Hi Willie,
Thanks for your help.
In the meantime I have debugged some more and found that the actual cause was the call transaction XD02 not returning a success or failure message. I would have expected message F2 056 (changes have been made) as the result of the call transaction.
I have created a simple recording via SM35 for tcode XD02 and it did not return any message at all (whilst sy-subrc was 0).
I have set breakpoints on all places where message F2 056 is created and found out that in include MF02DFS0 there is a perform VERBUCHUNGSAUFRUF and that has perform ADDITIONAL_DATA_SAVE.
That perform searches for implemented BADI's and it appeared that an active BADI is causing the issue. If I skip the BADI via debugging all works well.
Kind regards,
Miguel