interior lights

on my 24bhs the interior lights are almost flat to the ceiling. how do you open them to check and or replace the bulb?
also have replaced the mattress with one from amazon, it is a travel happy short queen. made in the us. 8 inches thick. sleeps like my leesa at home.

If there's a glass lens about 4" in diameter, you can pull it down about an inch so you can hold the "can" while twisting the lens counter-clockwise (looking up). Spring clips hold it in the ceiling. That type of lens only takes a slight twist to get it off.

That's the way the incandescent and halogen lights have been.

On your 2018 trailer, those lights may be just a lens covering a circuit board that has LEDs soldered to the board. If the LEDs fail, you buy a new fixture.