API to Change Transaction Type in ReSA

There were over 3000 transactions that were incorrectly recorded in ReSA and were subsequently generated POSUPLDs. The actual sale was just actually 1000 transactions. We need to void the excess 2000 transactions in ReSA so that the inventory would revert back to the normal count.  We are asked to do the change programatically since our business team does not have the capacity to void all of these manually. is there an existing API that can somehow reverse the transactions from Sale to Return? thank you.