On the external payment I created below which will replace the standard IFS BACS format for a UK customer, how do I add a function to sum the total of column “payment_amount” which is a number data type (detail tab). Without sum, the payment file output will list all supplier invoice while the file sent to bank should sum invoices to pay as one lumpsum per supplier. I did a search to list of available main functions, could not find sum function. The closest function I can find is “Add”. Am I missing something?
