This issue has been the cause of my PS5 and even XboxOne failing to when it comes to team play. I see the symptoms in the logs but can't explain why or how to fix it. Here are the details:

1. UPnP is turned on and my PS5 NAT is Type 2. However, I can't get into any group games. Otherwise the Playstation Network is working great
2. I do have a site-to-site VPN to one of the players in my group. But it's not for gaming and have rules only allow specific ports allowed for backups.
3. In the logs I see my PS5 trying to connect to the remote site's PS5 but getting blocked because I don't have a rule allowing that traffic.

I find it odd that my PS5 knows the address of the Remote PS5. How is this even possible?

Does this have something to do with the UPnP?

Cordially,

PowerExtreme