Over a 20 year period, my construction company has installed a literal boat load of steel doors and frames in near every commercial and industrial application you could imagine. Including Federal Buildings and Military Bases.
In in an exterior wall application, the lock set or deadbolt, hinge butts, and the actual steel door itself are the weak links. And in that order.
In an interior wall application, the bottom frame anchors, wall base plate anchors, and the enclosing wall itself are the weak links. And in that order.
There are of course exceptions. But your best bet is to sit down on your butt and persistently kick the bottom corners of the frame at the wall. If there are any heavy objects in the room, place them behind you to leverage against. Don't wear yourself out too quickly or hurt yourself. Just good hard jolts with your heals. You will be surprised at how effective this is.
If the interior walls are concrete, treat your attack the same as an exterior wall.
If the exterior walls are steel/wood stud with drywal and exterior siding, treat your attack the same as in interior wall.
This all applies only if the walls surrounding the door can't be easily cut or kicked through.