I'm on an inexpensive LG Stylo 2V, my pokemon character seems to error quite a bit at gyms. Maybe don't submit your raid pass unless you know your avatar isn't pacing around looking for an accurate GPS signal. I'm under the impression they sometimes apply that error to deter careless remote spoofers.
Raids always crash...
I have always the same problem. I want to attack a raid boss (magicarp, bayleef,... the simple ones, since I am almost always alone at raids... so I hope the legendaries will come available/attackable via another route later), so ok: Raid pass, wait 108 seconds (I never change attackers), I see the arena appear and the 2 opponent pokemon, GOOOOO... crash and I get the Raid start screen again. Again: want to battle (luckilly pass is still valid), 108 seconds, GOOO ...zip. And again... Even restarting the app don't help. First I thought this would happen only for raid bosses that need more attackers, but no. THis happens for most of the raids I want to start. This gets very frustrating, and now even more, since raids are no more announced (via the egg on top of gym) but immediately start, so there is even no more warning that you will not be able to attack a gym...
I'm PTC on Android with version 0.69.1
Answers
autotime: turn it off
or it might be turn it on.
next time you crash, what ever your autotime ia, flip to the other setting.
This exact same thing was happening to a friend of mine, the corrected setting of autotime fixed it.
And always keep checking, for her it would set back to the bad settings. She I think has a galaxy.
Set your phone to use network time.
If you don't use network time, the clock will be a few seconds off of the actual time, and this results in it trying to start the raid. I suspect it causes the game to try to start the raid when the server expects you to still be in pokemon selection screen or something like that.