Sounds like you’re caught in the middleman loop, so there’s the shake shack point of sale system processing the refund which has to go through Ubereats (still confused why they’re involved) and then your bank/card company, most refunds are not immediate (as LITTLE as 30 days in some cases) and your case has multiple stages. The main fuck up in this story is how much time you have spent seeking a refund over getting the wrong fries but sounds like you’ve come out ahead with bonus fries