epos office and till programming

managed to get the discount button on till and its says -20% but doesnt actually take anything off bill just say discount -20% but the cash value discount is 0.00

using the adjust percentage button as its the only one the would take % instead of fixed amount

Set the Percentage %1 to 20% and ensure it's tagged as negative. Can't look for flag numbers, but they're not hard to find.