DPU warning: Unable to rollback against JDBC Connection

Dear DPU-experts,
I updated an existing project on controlling instance (One Data version 7.0.1) with an export from our delivery-instance (same One Data version).
When updating I get the following warning for a workflow, that is used as microservice-workflow and creating a hash-key from specific columns.

[WARN]  Unable to update workflow 73c2c8a6-3e88-461c-a442-59aaab6627cd in version 2 (ODBErrorCause.ODBErrorCauseException: TransactionSystemException: Could not roll back JPA transaction; nested exception is org.hibernate.TransactionException: Unable to rollback against JDBC Connection)

Do you know what this error-message indicates? On the second update the message did not appear, and the update was successful without warnings.
Thank you