invoice data in RA_CUSTOMER_TRX table shows the value of PRINTING_PENDING = Y. and invoice has a PR

Hello Experts , 

we have an issue recently and resolved with data fix but need to know Root Cause for the below issue. 

There are 3 AR Invoices which print repeatedly with each scheduled

invoice print batch.  The concurrent request for AMERICAN

ENGLISH- (FR: Customer Invoice).  This program is submitted by the FR:

Customer Invoice(Customer Language Specific) program dependent on

language.  The concurrent id includes the 3 repeated invoices at

the start of the batch followed by the newly generated invoices which

are ok.

Review of the invoice data in RA_CUSTOMER_TRX table shows the value of

PRINTING_PENDING = Y.  Each invoice has a PRINTING_COUNT = 25 as of