UberEats costing me my lunch!

I have made an order through ubereats using ubereats voucher, but I have been having trouble when checking out and making payment as I am using ubereats voucher the order doesn't go through. I have been communicating this through the help line on the app since the 2 of June 2021. till date, I have not recieve any response till today this has inconvenience me so much that I seriously want my refund.