LED Recessed lighting trim stuck
In almost every case, recessed lighting trim is held in place by springs on two sides of the unit. If you can get purchase on the edges, pull down on opposite sides. The unit should lower by several inches.

If you cannot get a grip, you could pry first one side, then the other with a thin plastic putty knife or a plastic spatula. Once you can grip it, again pull down a few inches.

You can then usually release the springs holding the unit to the ceiling. Be careful, because on many LED units, the trim and lighting portions are integral, and they may have wiring going up into the fixture that may need to be disconnected.