Spindle Orientation

Couple things come to mind.

Did it really 'just stop' working?
How confident are you that nobody has either played with settings, or fiddled with the machine?

Without any photos, we can only guess on the setup. Could it be the encoder disc has spun on the spindle? It shouldn't but you never know. Is the encoder on the actual spindle, or is it belt driven of to the side?

Has somebody altered the spindle orientation settings?
A quick search of the manual reveals there should be a custom M19 macro to orientate the spindle, which is called automatically after the M17 macro, which itself is called prior to an M6 command.

Thanks Nick, I understand.
The company have contacted two service engineers who have said they will do it but neither have tuned up, so I’m not sure what to do next ?

Hi m c, yes the machine was half way through a job and came to a tool change when the fault occurred. As for the other questions I really don’t know that’s why we need someone with more knowledge than me to take a look