Uber eats promotional voucher from fnb and cancelation of my order

Im disgusted by the lack of service received by an employee of uber eats as well as uber eats on its own his name was ali i have the chat i ordered from fish aways Musgrave on the 28th December my order came to 129.90 i was supposed to get 75 of it but apparently it not go through i tried canceling the order but was told my account will fall into arrears what nonsense for food that i never received im horrified its the first ive heard of this.now voucher is expired. Uber eats ur service and agents and not of any help im disgusted Ali goes on to say i don't have any vouchers on my profile i checked and i had one left i need an explanation.