Engine Dixon RAM 50 PTO stuck?

I have a 2004 Dixon RAM 50 ZTR and I was mowing with it yesterday
and turned off the PTO and when I attempted to turn the PTO back
on it did not engage.

I Shut the motor off and now it will not turn over... I suspect that the
PTO interlock switch is stuck.

Any suggestions on how to troubleshoot this problem and are there
any service documents available for this model?

Thanks

Engine Dixon RAM 50 PTO stuck?