Are you using the piece of wood/plastic guide to set the height of the laser correctly? With the guide on your workpiece, raise the bed (using the Z) until the guide profile clips into the tube of the laser

Has the bottom of the laser tube been nudged? The most bottom piece is attached with magnets, gently pull it down and then reattach and the magnets should re-align it.

Has someone messed with the setting on the LCD screen - do they both read 100/100? Sometimes people play with it and don’t set it back.

Is the mirror clean? It can be cleaned with isopropyl alcohol and a cotton bud

Are both of the plastic clips still on the end of the laser?

If your material is being scorched, have you checked the lens is in the right way? The concave side should face the workpiece: