Wslf

I just bought a white super slim ps3 and the disk won’t spin. When I close the tray it makes some sounds for a couple of seconds like it wants to move but then stops. I’m not sure if it’s the lens or the motor.. does anyone know if I should replace the laser or disk motor? The ps3 was super dirty when I got it so can it maybe be the dust that’s preventing it from moving. ( sometimes the tray doesn’t close all the way so can this be part of the problem as well) ?