Adding AP Invoices to group with BPM

Hi Team

I am looking at using a UD table to invoke my AP creation BPMs. I can create the new group fine but when I try to create the AP Invoice Header it is not working. There are no error messages

I am using the GetNewAPInvHedInvoice (passing in my variables) and then doing a UpdateMaster. I must be missing a method or two inbetween. Could anyone point me in the right direction. I would prefer to do it in the rather BPM designer than go down the custom code route.

I am passing through all these variables Company, GroupID, VendorNum, InvoiceNum, InvoiceDate ScrDocInvoiceVendorAmt, TermsCode, PMUID, TaxRegionCode.

Any help would be much appreciated. See attached for the BPMs so far.APInvoiceBPM_Customer (112.3 KB)