Credit Card decline after it had been approved: FI***

I app**** for a credit card on the 18th of February 2021, i was told the process will take three business days i then followed up after a week and was told my application was approved and i should wait delivery of the cards. another two weeks passed on the 8th of March 2021 i called the bank and was told the cards are on their way and should expect them in two days time. Then on the two days time promised i received a decline sms, i honestly don't understand what level of incompetence and treachery this is, taking someone on a run around for a month and then simply declining their application, and just when i was seriously considering to move all my banking to them they gave me a good reason not to