There can be several reasons for your amp not putting out sound, including no power to your amp, frayed or loose cables, a turned-down volume knob, a faulty or disconnected pedal, a malfunctioning power supply, or internal problems in the amp itself. Make sure the settings on the amp are fine, and that it is plugged in and switched on. If the problem persists, you will likely need to take your amplifier to a professional to get it looked at and fixed.