Your new post shows that @PrePersist is invoked as expected when you call persist.
It is unclear what methods in JPA the JpaRepository uses. Maybe merge is used instead of persist and it may affect which event methods are invoked. You may want to check @PostPersist and other callbacks as well.
> it would be MUCH more simple when you would have been used my project as proposed.
Clearly it would be more simple for you, but unfortunately we cannot offer this service of debugging and investigating issues in user projects (obviously as part of our free support), as we do not have unlimited resources. We hope for your understanding and good luck with whatever you choose.