Microwave not working. The microwave suddenly will not work. The clock is on, the interior light

Question

The microwave suddenly will not work. The clock is on, the interior light works but the only key that makes a noise is the stop/clear.I thought it accidentaly was locked and tried holding numerous keys- the stop/clear key eventally put a little L on the screen even though the lock sign is on the start key. I tried unplugging. I have not figured it out + I no longer have the manual since I've never needed it in the 8+ years I've had it.