Hello

we currently have a problem with our license server.
It runs on a VM in our location 1. Everything works fine from my workstation in the local network. 
Unfortunately, the colleagues from location 2 can no longer access the license server, although everything else is working properly. 
All ports are open in our intranet, i.e. between the locations, the name resolution works, ping works, remote desktop on the server works, ... 
in short, everything works, everything except the license server. 
It all worked for years without any problems and now it is no longer possible across locations.
One difference is: Before the license server ran on an old VM under Win 2012 now on a new VM under 2019. 
Normally I would blame this change, but the server works perfectly when it ius accessed from local network. From location 2 both servers are not working.

Any ideas what we could do?

License server version: 8.5.5.0015

Client: Passolo 2016, CollaborationEdition; Version: 16.0.412.0