Hello
The possible causes are:
1 - TMSADM user must be locked in the 000 client
2 - The password for the TMSADM user maintained in the RFC TMSADM@SID.XXX must be incorrect.
3 - There must be some password restrictions enabled on the system and because of this the password maintained in the RFC for the TMSADM is not in accordance with the password rules.
Do an authorisation check for the RFC's for the TMS from all the systems in the transport.
Regards
RB