Question about the requirement for goods issue from a delivery (VOFM)

Question

Dear all
※Please note that this is related to the credit limit check.
I am trying to set up the SAP system, so that if the maintenance contract (rental document) is billed at least once,
the system would allow the user to bill the customer regardless of the credit usage (ex. 150%).
So I created the following routine for the credit check (in VOFM).
IF XVBAK-AUART = 'ZMZZ'.    --> Please note that ZMZZ is the document type of our rental document
   LOOP AT XFPLT.
       IF XVBUK-FKSAK = 'B' or XVBUK-FKSAK = 'C'.
We will not do any credit limit check for this item line.
            MOVE CHARX TO BYPASS-SECURITY.
            MOVE CHARX TO BYPASS-STATIC_LIMIT.
            MOVE CHARX TO BYPASS-DYNAMIC_LIMIT.
            MOVE CHARX TO BYPASS-DOCUMENTVALUE.
            MOVE CHARX TO BYPASS-CRITICAL_FIELDS.
            MOVE CHARX TO BYPASS-REVIEWDATE.
            MOVE CHARX TO BYPASS-OPEN_ITEMS.
            MOVE CHARX TO BYPASS-OLDEST_OP.
            MOVE CHARX TO BYPASS-DUNNING_LEVEL.
            MOVE CHARX TO BYPASS-USER1.
            MOVE CHARX TO BYPASS-USER2.
            MOVE CHARX TO BYPASS-USER3.
            EXIT.
      ENDIF. 
           EXIT.
   ENDLOOP.
ENDIF.
Now, with the routine above, it became possible to bill customers regardless of the credit usage.
However, when we try to ship (posting goods issue) the item for that maintenance contract, when the credit usage exceeds 100%, the system rejects it with the error message below.
<Error message>
Static credit check: credit limit exceeded
Now, I want to set up the system, so that if the posting goods is for the item which satisfies the following condition,
the system would not reject the posting due to the error above.
<condition>
1. The item is for the maintenance contract which was billed at least once --> this means that this is not a new contract
※Please note that for new maintenance contracts (which is not billed even once),  the system should not allow to post goods 
   issue if the credit usage exceeds 100 %.
I looked into VOFM, and found out that we are using the following routines for posting goods issue.
<system routine>
13
<user routine>
113
But I didn't know where the error (Static credit check: credit limit exceeded) came from.
Could you tell me how to find (or where to modify) a location where I can make the modification in order to
satisfy our requirement?
Thank you very much in advance

Answer 1

Dear all
I was able to solve the problem by setting up the credit check routine for delivery notes, and assign it for "No credit check" field
in the automatic credit control (OVA8).
So, thank you for your help, everyone
Takashi