Unable to online with others via StarLink

Hello everyone, my brother and myself where playing online together and everything was fine. After though he installed 2 DLC’s he was missing, something change in the base game. He is no longer able to play online with anyone, pretty sure it’s something conflicting between the game and his Internet which in this case is StarLink. Does anyone know a way to fix this or is there potential a patch coming out soon that may address this issue.

Thank you

Everyone needs to have the same dlc to play together.

That’s what we were doing, getting the same DLC’s, but it won’t work now.

Is everyone on the same version?
Do they get an error message? If so, what’s the message?