OpnVPN Site-to-Site RemoteSite not reachable

[TheSnats]

Hello everyone,

at a customer we can't address the public IP address from the outside and that's why I decided to use the server / client concept at OpenVPN to build a site-to-site tunnel.
I did the configuration according to these instructions: https://docs.opnsense.org/manual/how-tos/sslvpn_s2s.html

The tunnel is also established and I can ping the two gateway addresses. Unfortunately I can't get into the customer network 10.50.100.* and can't explain why. The routes are entered automatically.
I have attached the configuration as a screenshot.
Has anyone had a similar experience and know what needs to be done here?



ClientConfiguration:

ServerMode: Peer to Peer
Protocol: UDP
Device Mode: tun
Interface: WAN
RemoteServer: our Public IP
IPv4 Tunnel Network: 10.10.5.0/30
IPv4 Remote Network: 172.25.3.0/24