Hi, I am new to here and looking for some guidance. Background: We are a small ISO 9001:2015 certified company who provide services to our client. An NC request has been issued to me (as the Quality Manager) from one department (accounts) to another department (operations) as a signed PO is not available to allow them to invoice the work. The client's contract states that a signed PO is required for invoicing. The PO is issued by the client and is not an internal document. Now, the client hasn't issued an NCR, this is an internal request. As our client requirements are all different and vary so much, particular client requirements are included in our procedures. What I am struggling with, is what to issue the NC against. Any thoughts?