Camel-Netty4-HTTP throws exception with async processor containing CompletableFuture

When using async processor which contains completable future callback I get the below exception. the exception can be seen when callback is being called. i.e: in the async processor process method I have something like this:
@Override
public boolean Process(Exchange exchange, AsyncCallback callback){
completableFuture = myApi.getCompletableFuture();
completableFuture.whenComplete((response)->

{ exchange.setProperty("abc", "def"); callback.done(false); }

)
return false;
}

Thx, Amit.

Exception:
Caused by: [org.apache.camel.TypeConversionException - Error during type conversion from type: java.lang.String to the required type: byte[] with value [Body is instance of org.apache.camel.StreamCache] due io.netty.util.IllegalReferenceCountException: refCnt: 0]
org.apache.camel.TypeConversionException: Error during type conversion from type: java.lang.String to the required type: byte[] with value [Body is instance of org.apache.camel.StreamCache] due io.netty.util.IllegalReferenceCountException: refCnt: 0
at org.apache.camel.impl.converter.BaseTypeConverterRegistry.createTypeConversionException(BaseTypeConverterRegistry.java:567) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.impl.converter.BaseTypeConverterRegistry.convertTo(BaseTypeConverterRegistry.java:131) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.impl.MessageSupport.getBody(MessageSupport.java:72) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.impl.MessageSupport.getBody(MessageSupport.java:47) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.component.netty4.http.DefaultNettyHttpBinding.toNettyResponse(DefaultNettyHttpBinding.java:350) ~[camel-netty4-http-2.14.1.jar:2.14.1]
at org.apache.camel.component.netty4.http.handlers.HttpServerChannelHandler.getResponseBody(HttpServerChannelHandler.java:302) ~[camel-netty4-http-2.14.1.jar:2.14.1]
at org.apache.camel.component.netty4.handlers.ServerChannelHandler.sendResponse(ServerChannelHandler.java:152) ~[camel-netty4-2.14.1.jar:2.14.1]
at org.apache.camel.component.netty4.handlers.ServerChannelHandler.access$100(ServerChannelHandler.java:39) ~[camel-netty4-2.14.1.jar:2.14.1]
at org.apache.camel.component.netty4.handlers.ServerChannelHandler$1.done(ServerChannelHandler.java:140) ~[camel-netty4-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.Pipeline$1.done(Pipeline.java:145) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:428) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.management.InstrumentationProcessor$1.done(InstrumentationProcessor.java:81) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.ChoiceProcessor$1.done(ChoiceProcessor.java:72) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:428) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.management.InstrumentationProcessor$1.done(InstrumentationProcessor.java:81) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.SendProcessor$1.done(SendProcessor.java:131) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.Pipeline$1.done(Pipeline.java:145) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:428) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.management.InstrumentationProcessor$1.done(InstrumentationProcessor.java:81) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.ChoiceProcessor$1.done(ChoiceProcessor.java:72) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:428) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.management.InstrumentationProcessor$1.done(InstrumentationProcessor.java:81) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.SendProcessor$1.done(SendProcessor.java:131) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.Pipeline$1.done(Pipeline.java:145) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:428) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.management.InstrumentationProcessor$1.done(InstrumentationProcessor.java:81) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.ChoiceProcessor$1.done(ChoiceProcessor.java:72) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:428) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.management.InstrumentationProcessor$1.done(InstrumentationProcessor.java:81) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.SendProcessor$1.done(SendProcessor.java:131) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.Pipeline$1.done(Pipeline.java:145) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:428) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.management.InstrumentationProcessor$1.done(InstrumentationProcessor.java:81) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.SendProcessor$1.done(SendProcessor.java:131) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.Pipeline$1.done(Pipeline.java:145) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.CamelInternalProcessor$InternalCallback.done(CamelInternalProcessor.java:251) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.processor.RedeliveryErrorHandler$1.done(RedeliveryErrorHandler.java:428) [camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.management.InstrumentationProcessor$1.done(InstrumentationProcessor.java:81) [camel-core-2.14.1.jar:2.14.1]
at com.companyXXX.ip.frontend.facade.agent.legacy.translator.processors.ZZZAsyncProcessor.lambda$process$0(ZZZAsyncProcessor.java:39) [facade-agent-legacy-translator-0.1.2.0-SNAPSHOT.jar:na]
at com.companyXXX.ip.frontend.facade.agent.legacy.translator.processors.ZZZAsyncProcessor$$Lambda$26/30716559.accept(Unknown Source) [facade-agent-legacy-translator-0.1.2.0-SNAPSHOT.jar:na]
at java.util.concurrent.CompletableFuture$AsyncWhenComplete.exec(CompletableFuture.java:648) [na:1.8.0_05]
at java.util.concurrent.ForkJoinTask.doExec(ForkJoinTask.java:289) [na:1.8.0_05]
at java.util.concurrent.ForkJoinPool$WorkQueue.runTask(ForkJoinPool.java:902) [na:1.8.0_05]
at java.util.concurrent.ForkJoinPool.scan(ForkJoinPool.java:1689) [na:1.8.0_05]
at java.util.concurrent.ForkJoinPool.runWorker(ForkJoinPool.java:1644) [na:1.8.0_05]
at java.util.concurrent.ForkJoinWorkerThread.run(ForkJoinWorkerThread.java:157) [na:1.8.0_05]
Caused by: org.apache.camel.RuntimeCamelException: io.netty.util.IllegalReferenceCountException: refCnt: 0
at org.apache.camel.util.ObjectHelper.wrapRuntimeCamelException(ObjectHelper.java:1364) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.util.ObjectHelper.invokeMethod(ObjectHelper.java:1006) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.impl.converter.StaticMethodTypeConverter.convertTo(StaticMethodTypeConverter.java:59) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.impl.converter.BaseTypeConverterRegistry.doConvertTo(BaseTypeConverterRegistry.java:276) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.impl.converter.BaseTypeConverterRegistry.convertTo(BaseTypeConverterRegistry.java:114) ~[camel-core-2.14.1.jar:2.14.1]
... 56 common frames omitted
Caused by: io.netty.util.IllegalReferenceCountException: refCnt: 0
at io.netty.buffer.AbstractByteBuf.ensureAccessible(AbstractByteBuf.java:1187) ~[netty-buffer-4.0.24.Final.jar:4.0.24.Final]
at io.netty.buffer.AbstractByteBuf.checkReadableBytes(AbstractByteBuf.java:1170) ~[netty-buffer-4.0.24.Final.jar:4.0.24.Final]
at io.netty.buffer.AbstractByteBuf.readBytes(AbstractByteBuf.java:676) ~[netty-buffer-4.0.24.Final.jar:4.0.24.Final]
at io.netty.buffer.CompositeByteBuf.readBytes(CompositeByteBuf.java:1461) ~[netty-buffer-4.0.24.Final.jar:4.0.24.Final]
at io.netty.buffer.CompositeByteBuf.readBytes(CompositeByteBuf.java:40) ~[netty-buffer-4.0.24.Final.jar:4.0.24.Final]
at org.apache.camel.component.netty4.http.NettyChannelBufferStreamCache.read(NettyChannelBufferStreamCache.java:69) ~[camel-netty4-http-2.14.1.jar:2.14.1]
at org.apache.camel.component.netty4.http.NettyChannelBufferStreamCache.read(NettyChannelBufferStreamCache.java:54) ~[camel-netty4-http-2.14.1.jar:2.14.1]
at org.apache.camel.util.IOHelper.copy(IOHelper.java:196) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.util.IOHelper.copy(IOHelper.java:169) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.util.IOHelper.copy(IOHelper.java:165) ~[camel-core-2.14.1.jar:2.14.1]
at org.apache.camel.component.netty4.http.NettyChannelBufferStreamCache.writeTo(NettyChannelBufferStreamCache.java:84) ~[camel-netty4-http-2.14.1.jar:2.14.1]
at org.apache.camel.converter.stream.StreamCacheConverter.convertToByteArray(StreamCacheConverter.java:102) ~[camel-core-2.14.1.jar:2.14.1]
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method) ~[na:1.8.0_05]
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62) ~[na:1.8.0_05]
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) ~[na:1.8.0_05]
at java.lang.reflect.Method.invoke(Method.java:483) ~[na:1.8.0_05]
at org.apache.camel.util.ObjectHelper.invokeMethod(ObjectHelper.java:1002) ~[camel-core-2.14.1.jar:2.14.1]
... 59 common frames omitted