Flowable stuck and didn't procceed

any advise why this exception happened
org.flowable.common.engine.api.FlowableOptimisticLockingException: JobEntity [id=1e0bcf09-90d7-11ea-8082-eab81a0aedf3] was updated by another transaction concurrently
at org.flowable.common.engine.impl.db.DbSqlSession.flushDeleteEntities(DbSqlSession.java:571) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.engine.impl.db.DbSqlSession.flushDeletes(DbSqlSession.java:526) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.engine.impl.db.DbSqlSession.flush(DbSqlSession.java:293) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.engine.impl.interceptor.CommandContext.flushSessions(CommandContext.java:191) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.engine.impl.interceptor.CommandContext.close(CommandContext.java:61) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.engine.impl.interceptor.CommandContextInterceptor.execute(CommandContextInterceptor.java:81) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.spring.SpringTransactionInterceptor.lambda$execute$0(SpringTransactionInterceptor.java:56) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.springframework.transaction.support.TransactionTemplate.execute(TransactionTemplate.java:140) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.spring.SpringTransactionInterceptor.execute(SpringTransactionInterceptor.java:56) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.engine.impl.interceptor.LogInterceptor.execute(LogInterceptor.java:30) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:56) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.common.engine.impl.cfg.CommandExecutorImpl.execute(CommandExecutorImpl.java:51) ~[acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.job.service.impl.asyncexecutor.ExecuteAsyncRunnable.executeJob(ExecuteAsyncRunnable.java:128) [acs-process-management.jar:0.0.1-SNAPSHOT]
at org.flowable.job.service.impl.asyncexecutor.ExecuteAsyncRunnable.run(ExecuteAsyncRunnable.java:116) [acs-process-management.jar:0.0.1-SNAPSHOT]
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149) ~[na:1.8.0_212]
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624) ~[na:1.8.0_212]
at java.lang.Thread.run(Thread.java:748) ~[na:1.8.0_212]

Hey @gihan,

That exception can occur when an async task is running too long (by default more than 5 minutes). Before a job is started it will try to lock the job. If the job is running for too long then the job will be unlocked and another thread might pick it up. This means that when the job finishes, it can’t be updated because it was already updated by another transaction.

Cheers,
Filip