There was server maintenance done to the game about 2 days ago. I gave my girlfriend my copy of Dark Souls 3 because I also had a digital version and I planned on helping her through the beginning area however ever time she tries to summon me it says failed to join session. We have tried the following things to no avail:
- Restart either Xbox
- Restart either router
- Change covenant
- Move summon sign.
We also tried to see if I could summon her and for me her sign won't even pop up.
A couple of side notes, we are both able to summon other people with ease, and we are able to be in each others parties.
Our setting are:
Cross-region play: Matchmaking ON
Password Matching: DOOM
Summon sign visibility: Unrestricted
Voice chat: Allowed
Player Name Display: Gamertag
Launch Setting: Play Online.
EDIT: I tried to play with her on another console and it let us play together.