Sonic Drive-In review: Customer service (gift cards)

I know there are problems with Sonic gift cards! This is a 2 year ongoing problem.
I do surveys every year for Rice University in Houston, Texas. Upon completion of the survey, we are given a $15 gift card through Tango. There are approximately 200 gift cards to choose from. I always choose the Sonic E gift card for doing the survey.
I know from past experience that the app will only allow five gift cards, after that if you want to add one you need to start deleting. If the gift cards have a balance, you will not be able to get rid of it and you cannot refill the cards so I was told last year if I wanted to delete one, I would have to make an order that would be down to the last penny so I could zero out the gift card and get rid of it to add another one. Just this, is the most ridiculous thing I’ve ever heard, but I did get past it. So this year, knowing I had five gift cards in the app I decided to make another account through the website so I wouldn’t have to mess with the app to try and delete a gift card.
I opened the account and transferred the gift card to this account for the $15 for completing the survey. A couple of days later I wanted to use this gift card and there was no money on it. How does this happen? Well, I’m just not sure but the young lady with Customer service told me that it had to be the third-party who was tango and that I needed to reach out to them to solve the problem. How in the world it could be tango? after I added the gift card it said there was $15 on the gift card. She was absolutely no help and I had spoken to the same young lady about other gift card problems in the app, and I won’t say her name. In the meantime, another customer service representative told me she would call Techniical Support and have them combine all of my gift cards into one in the app. It’s been going on two months now and that has not been done. I cannot tell you how frustrating this has been with Sonic for going ontwo years.
Sonic, do better! Retrain your people whatever it takes! just do better!