Case : When we are doing Program SAPF100 at the month end and do the posting thru the BDC session we find that the following Debit and credit posting gets duplicated. In the sense that these 2 line items are getting posted as a separate document and also as part of another document when we run the BDC session.
At present we are manually correcting it by reversing one of the documents (in which only these 2 line items are there) thru FB08.
Answer SAP allows you to run SAPF100 multiple times and every time it is run, it creates entries in the BDC, causing multiple documents to be created for the same transaction.
You may check your closing procedure documentation (provided by your implementor) to see whether there is duplication.
Else, the possibility is that two different users are running the same program.
This should be done only ONCE during the closing process.