Programmatic error: no parent scope execution found for boundary event

I have migrated from activiti (5.18.0) to flowable (6.1.2). The process definition also has changed a bit. We have added some boundary timer event to the user tasks. I am facing the below error

org.flowable.engine.common.api.FlowableException: Programmatic error: no parent scope execution found for boundary event
at org.flowable.engine.impl.bpmn.behavior.BoundaryEventActivityBehavior.executeNonInterruptingBehavior(
at org.flowable.engine.impl.bpmn.behavior.BoundaryEventActivityBehavior.trigger(
at org.flowable.engine.impl.interceptor.CommandInvoker.executeOperation(
at org.flowable.engine.impl.interceptor.CommandInvoker.executeOperations(
at org.flowable.engine.impl.interceptor.CommandInvoker.execute(
at org.flowable.engine.impl.interceptor.BpmnOverrideContextInterceptor.execute(
at org.flowable.engine.common.impl.interceptor.TransactionContextInterceptor.execute(
at org.flowable.engine.common.impl.interceptor.CommandContextInterceptor.execute(
at org.flowable.spring.SpringTransactionInterceptor$1.doInTransaction(
at org.flowable.spring.SpringTransactionInterceptor.execute(
at org.flowable.engine.common.impl.interceptor.LogInterceptor.execute(
at org.flowable.engine.common.impl.cfg.CommandExecutorImpl.execute(
at org.flowable.engine.common.impl.cfg.CommandExecutorImpl.execute(
at org.flowable.engine.impl.asyncexecutor.ExecuteAsyncRunnable.executeJob(

Please help me in solving this issue. What needs to be done for a smooth migration?

Did you add the flowable 5 compatibility jars? Old process definitions should run against the embedded v5 engine, not against 6.

I have added the flowable 5 migration jars. I have migrated the old process instances using SetProcessDefinitionVersionCmd to the latest process definition. As a result they aren’t marked as v5 and run against v6 engine. How do I make them run against the V5 engine ?

I have also been facing this issue. Not sure how to go about it.

I had the same problem ,how to solve it?
My version is 6.4.2