My Voucher didnt work always - Consumer Complaint for Food Panda Philippines

My voucher that you have been issued is invalid. Now i contact you through email yet they keep.on asnwering me that the voucher is ok. But i keep on trying even reinstall the app but its still not working! Now im asking for a new code but they dont want to send me one. And it gets me upset so much! I cant purchase my order coz the Voucher is invalid.