Can’t remember a movie about a group of special forces trapped in a bunker/base while under attack.

So all I remember is that this movie is about a base of some special forces group. For some reason the base is stormed by another group of attackers.
The base has one entry which is a big large bullet proof door. At the end the leader steps out of the base and negotiates with the attackers.
The entire movie is about this base getting attacked, but I can’t seem to find the movie just by searching keywords.

I remember there is an armour room, ammo room, an IT room and more.