Join Script Wordpress fail, exitcode 51

Dear all,
running UCS 4.4.4 errata642 and try to install Wordpress. Joinscript fails with Exitcode 51.

RUNNING 50wordpress.inst
2020-06-29 17:33:13.700096948+02:00 (in joinscript_init)
Object exists: cn=services,cn=univention,dc=home
Object exists: cn=Wordpress,cn=services,cn=univention,dc=home
WARNING: cannot append Wordpress to service, value exists
No modification: cn=somehostname,cn=dc,cn=computers,dc=home
Object exists: (group) : wordpress-editors
Object exists: (group) : wordpress-authors
Object exists: (group) : wordpress-contributors
Object exists: (group) : wordpress-subscribers
univention-join-hooks: looking for hook type "join/post-joinscripts" on somehostname.home
Found hooks:

Mo 29. Jun 17:33:24 CEST 2020
univention-run-join-scripts finished

Tried the installation multiple times, deinstalled, removed and cleaned up as well. Does anyone have a hint for me where to search for the reason?

Used workaround found in