unable to join a friend's servers

I can't join my friend's (Cosmodog) servers. She also left a error report. We played together in the morning and that evening I start getting the message that the server was not responding. She also can't join my server but we can join other people's. We both are on ps5. Also when my friend, Cosmodog, created a new world, and I was also unable to join that one. We tried a world with friends only, no password, password, and just open to anyone, but nothing worked.