550S spindle issues

Hey everyone, have a harrison 550S Alpha lathe with GE fanuc and alpha control. Having issues with the fanuc side as of about 2 weeks ago the spindle will not seem to spin between 600-1400 rpm as in the speed range seems to be missing. In the alpha side of the machine the spindle and spindle control works perfectly fine but in fanuc if i do an MDI M03 S1000 it will spin at 1400rpm. Also get error 1015 guard over-ride relay fault

Anyone had this issue or can anyone steer me in the right direction to get it sorted?

Pic attached