I have been having issues with invoicing PO's and then doing the day end. Yesterday I invoiced a purchase order, went to do the day end and the module locked up. I have done data integrity checks, it sees some error with the PO, says it is fixed but when I go to do day end again, that PO is still there and locks up the module every time.

Since the module can not complete the day end, everyone else is locked out of the module. I need help fixing this ASAP please

Without knowing which version of PO there is no starting point to assist you. In any event most likely an expert would need to actually look at the data.

The best way to get immediate assistance is to contact your Adagio consultant.