DataException Only Struct objects supported with CamelRabbitmqsourceSourceConnector

[Dr10s]

Hello. I m try to use org.apache.camel.kafkaconnector.rabbitmqsource.CamelRabbitmqsourceSourceConnector.
I send simple json in rabbitmq queue like { "id": 14 } and in kafka connect i take null message key.

So, i has set valueToKey transformer but kafka-connect throw exception DataException: Only Struct objects supported for [copying fields from value to key]

Can sameone suggest me, what i need do for work with message data like simple json ojbect (without schema)?

Stack Trace:
trace: "org.apache.kafka.connect.errors.ConnectException: Tolerance exceeded in error handler\n\tat org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndHandleError(RetryWithToleranceOperator.java:223)\n\tat org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execute(RetryWithToleranceOperator.java:149)\n\tat org.apache.kafka.connect.runtime.TransformationChain.apply(TransformationChain.java:50)\n\tat org.apache.kafka.connect.runtime.AbstractWorkerSourceTask.sendRecords(AbstractWorkerSourceTask.java:386)\n\tat org.apache.kafka.connect.runtime.AbstractWorkerSourceTask.execute(AbstractWorkerSourceTask.java:354)\n\tat org.apache.kafka.connect.runtime.WorkerTask.doRun(WorkerTask.java:189)\n\tat org.apache.kafka.connect.runtime.WorkerTask.run(WorkerTask.java:244)\n\tat org.apache.kafka.connect.runtime.AbstractWorkerSourceTask.run(AbstractWorkerSourceTask.java:72)\n\tat java.base/java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:515)\n\tat java.base/java.util.concurrent.FutureTask.run(FutureTask.java:264)\n\tat java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1128)\n\tat java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:628)\n\tat java.base/java.lang.Thread.run(Thread.java:829)\n
Caused by: org.apache.kafka.connect.errors.DataException: Only Struct objects supported for [copying fields from value to key], found: [B\n\tat org.apache.kafka.connect.transforms.util.Requirements.requireStruct(Requirements.java:52)\n\tat org.apache.kafka.connect.transforms.ValueToKey.applyWithSchema(ValueToKey.java:81)\n\tat org.apache.kafka.connect.transforms.ValueToKey.apply(ValueToKey.java:67)\n\tat org.apache.kafka.connect.runtime.TransformationChain.lambda$apply$0(TransformationChain.java:50)\n\tat org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndRetry(RetryWithToleranceOperator.java:173)\n\tat org.apache.kafka.connect.runtime.errors.RetryWithToleranceOperator.execAndHandleError(RetryWithToleranceOperator.java:207)\n\t... 12 more\n"