Ideas
Tried to get my cousin to play the free trial, we managed one game in the last 2 days before it just kicks him back into the lobby. He enjoyed the one game he could play. Unfortunately he hasn't the time to wait around resetting the game and trying again to no avail each time and moved on to playing something else.
Platforms in your party - multiple PCs on Steam, one on PS5.
Cross-play setting is enabled for all
Everybody has had the issue from one time to another, regardless of platform. Mostly PC party with no PS5. PC and PS5 has only worked once, out of about 20 attempts, and it was the first try
This bug has happened to me numerous times with friends all on PC, they all quit playing after the first few weeks when no hotfixes came out. My cousin is on PS5 and it's doing the same. Known issue from Beta, was still in on launch day, and has not been fixed 5 months later. Of all the issues that never got addressed with a day one hotfix never mind in the first actual patch, this is the most game braking for people to be able to play with friends.
Cannot imagine it makes for a successful trial, unless they just want individuals to play the game on their own. Shame, as Battlefield was always about teamwork. Back to the other crossplay games we can play together like Space Marine 2 or Arc Raiders, without issues and working from day 1. If Battlefield 7 comes out in October of this year, then I shall not be buying it unless everything that has hampered this game is fixed and we get proper big maps like in the older Battlefield games. Although if they aim for a yearly release it it'll end up as untested slop like CoD, a shop with some sort of a game attached.