Multiplayer PS4 not working

When inviting my friend or joining his game we both get the same issue, the screen says joining and it stays there forever. That’s pretty much it we can’t join each others games. We have done it 2 times before so it does work sometimes but repeatedly trying doesn’t seem to help.
o closed game ( only way to do anything after attempting to join)
o restarted ps4 (no effect)
o tried each others games (same result)

In another topic, dev responded to it;