1) Blown fuse: Check the fuse box for a blown fuse that controls the power supply to the mirrors. If you find a blown fuse, replace it with one of the same amperage.
2) Faulty switch: The switch that controls the mirrors may be faulty. Try pressing the switch several times to see if it works intermittently. If the mirrors work sometimes but not others, the switch may need to be replaced.
3) Wiring issues: There may be a problem with the wiring that connects the switch to the mirrors. Check the wiring for any breaks or loose connections.
4) Motor failure: The motors that move the mirrors may have failed. If you do not hear a sound when you press the switch, this may be the case. The motors may need to be replaced.
If you are not comfortable troubleshooting these issues yourself, it is best to take your vehicle to a qualified mechanic for diagnosis and repair.
