I see similar posts here about this. But my issue seems to be slightly different.
Repeatedly during online play with friends one of the players will get downed and put into FFYL. Any one of the other players will rush over to start the revive process. Upon reaching the downed player one of two different things happens.
They get within range of the downed player and no on screen notification to press X to revive is displayed. This can happen anywhere from just being a few feet away or literally right on top of the player. Looking directly at the downed player. And button mashing to try and get it to work only compounds the problem.
Or when they get there the press X notification displays, but nothing happens when it is pressed. Same distances and viewing angles as the other issue.
In both cases players have either died and respawned or just barely been revived. It is as if there is some “sweet spot” of distance and viewing angle that has to happen before the Revive will lock on and initiate.
Also, I agree with other posts about forcing a Revive to take priority over weapon pick ups and other controls tied to the X button. I have had it happen multiple times where I was trying to go in for a revive and instead the game not only picks up a weapon or gear, but dumps my equiped weapon or gear due to my backpack being full. Every time I have come close to having lost a good piece of equipment due to this issue.