Okay so now i removed the second lan entry and allowed the wg0 interface (192.168.250.x) as allowed ip from the service routers peer entry.
I can reach the office environment again, but cant ping from office to the service client. I have it on my roadmap to update all routers to the newest stable openwrt version.
But still how can this happen?
It has to be a routing issue. The handshake works. The Allowed IP's as well. I just dont get what could be wrong. As the routes in the routing table seem legit to me.
Okay i was able to trace the problem, it was a windows firewall problem. I actived network discovery and allowed the rules for icmp. But apparently i needed to create a dedicated icmp rule, to allow everything.
Sorry for wasting your time, but big thank you for the help anyways.
That's correct. The default Windows firewall is reasonably restrictive for incoming connections. That's a good thing. It does, however, mean that you'll need to set up specific rules on the Windows box if you do want it to accept the traffic you're trying to permit.