Ryobi 3404 DI Error e-002 help

A couple weeks ago I began getting an error which says "E-002 1st tower encoder. Encoder input error. There is no input from the encoder of 1st tower though the press is ON, OR the drive motor does not rotate although the CPU rotate the drive motor."

The error has caused my press to immobilize and I cannot rotate it. Sometimes after shutting down and restarting I can rotate and even run jobs, maybe 1 out of 5 restarts. I've even run the press a whole day recently but the following morning won't rotate it at all. It seems odd it will work sometimes, but not all the time.

When the error comes up on screen, it also says error on my inverter. I've tried swapping 1st and second encoders but the error code says "1st head encoder input error" either way. So not a faulty encoder? If anyone has any experience with e-002 and what I can do to get back up and running that would be greatly appreciated I've got jobs stacking up, and no idea what to try next, my service tech hasn't been getting back to me.