Lotto ticket not payout again by standard bank.

This is the second time whereby I have randomly checked a winning lotto ticket purchased on standard bank banking app and standard bank has failed to pay out. This is extremely concerning as I question how many other times and other people has standard bank not paid out. We trust that the verification process on the standard bank app would be correctly done. I have called ***as advised on the sms received but the consultant was confused on how to assist and transfered me to someone else, who never picked up. This call cost me more than the lotto payout. It seems like the safest option would be to just buy a ticket at a local machine.