BAPI to change Accounting Document Header
I have a requirement to go into an existing document (Billing Doc.) and change the Reference field (XBLNR). The business requirement is specifically to modify the BKPF-XBLNR field to contain a new reference. Is there a BAPI that can be used to modify accounting header details? All the accounting BAPI's I can find seem to be for posting a new record.
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