Yamaha EMX5000-12 powered mixer Faders not Working

[Big El Bass]

I have a Yamaha EMX5000-12 powered mixer and basically nothing works on it but the 2 AUX faders, no other faders or knobs are responding for each channel. I am using it as the mixer for the monitors for my church band and have it connected to the house mixer. Anyone know why this is not working. I have to include that it was previously dropped a few years ago and was partially reparied, but everything was still functional a few years later, today, it just stopped functioning and I can no longer set a mix for the musicians in the band for their monitors.