Bunkers in Warzone don't open?

I've found a key car several times and have been to different bunkers, but they just don't open, how does that work?

The map is also shown under my name below but I somehow can't use it.

Play on the Xbox

There are various bunkers on the map. Special bunkers that can only be opened with the keycard, bunkers that can't be opened at the moment and bunker 11 that can always be opened. I'll put a good video in here - it's about bunker 11 but it shows a map that gives you every bunker in its status.