PS4 doesn't accept discs

I just had a similar issue on a PS4 Slim, turned out to be dirt jamming up the grooves in the disc roller gears, it was causing the rollers to be sluggish and skip a little but ultimately didn’t have the torque to fully pull the disc in or eject it once forced in, this would also prevent the disc from settling all the way in so that the drive could properly read it. Once I cleaned out the gear connected to the rollers and carefully used a small jewelers flathead screwdriver and a nylon brush to clean the other two gears it works like new. Hope this helps others with this issue.