Closing Production Order error

Dear All

I am hoping someone can point me in the right direction. When we try to close some Production Orders we get a message "There is still a Purchase Requistion Commitment for Ord XXXXXXX" where XXXXXXX is the produstion order number. We get this when we try via COHV or via CO02.

I have checked the Compents Overview and made sure any O/S commitment has the deletion Indicator set, and also check MD04 for the components. So any help would be much appreciated.