Multiserver system inconsistent monitor information

Did update to 3.2 worked on nearly all servers, but not on the external server at 62.54.177.160. Same Problem as above. Sure I can do the same procedure as above, but this can not an solution.
At IP 62.54.177.160 I just have only a Fritz Box with Port forwarding. On the main site I have a full IPtables Firewall translation internal to external addresses and vice versa as i had on my old home, where everything worked fine for years. I think there is going some thing wrong in ISPconfig in exchanging the IP addresses between master ans slaves or I´m doing something wrong. Do not think nobody using ISPconfig does not have a situation as mine, that means Master and Slave are a different locations connected via the internet and have a Fritz Box on at least one site.

Thanks for any hint
Rainer