How can I trust you after this mess?

I have been embarrassed beyond belief by your institution and I wouldn't recommend someone else to support you. On many occasions I have spoken to you to change my limits, both temporary and permanent ones on your app. Still each time I have tried to use my credit card, the transaction won't go through, leaving me red faced, and I don't even want to use the same vendors as the impression left must be that I was trying to buy while having not enough money to pay for it. Your call centre has promised it will not happen again.