Misbehavior of DeleteCompletedInstance on Suspend

Hello,

I have workflow having UserTask as 4th step. When it executed the workflow suspended and logs table and bookmarks table have correct records. But workflowinstance has no record about that instance. Also IWorkflowExecuter or Dispatcher throws an error that saying the definition could NOT be found although it exists with the correct definitionId and version number. I tried to set persistence behavior both Suspended and Burst(default) nothing changed. I saw some issues about that case but none was telling the reason.

To check my flow here is what i wanted to do;
1. start the workflow with ContextProvider implementing my own model.
2. ForEach activity iterates the collection in my model.
3. While activity checks the input items quantity bigger than 0.
4. UserTask for making some human action over the items on hand.
5. SetVariable for setting the while's remaining
6. ForEach done outcome to end

1,2,3 worked, instance created and inserted to the instance table. After UserTask Executed in the logs table, console log says Deleting completed instances.... here is the fact i think.

I set DeleteCompletedInstances flag to false as a workaround, everything works fine for now.

Thank you in advance.