Credit Card dispute/ incorrect information and no resolution

called up on the 27th of November 2019 and was given incorrect information for a credit card limit increase by the agent who advised me to take up the limit increase with the higher interest rate and they will amend it within a few days, if i am unhappy i can go back to my previous (old) limit and interest rate. This was however false information that she provided as i called up a few days later wanting to go back to my original interest rate and limit. It is now been 4 weeks and this has not been resolved. The team leader listened to the call and advised me it will be reverted but only thing that was done by the FNB team was revert me to my old limit and not interest rate. is my own banker tried to extract me to pay a higher interest rate now after been incorrectly advised.. really disappointed especially been a Premier banker it takes 4 weeks to rectify a mistake made by your representative . this is mind blowing especially that it took 5 minutes for FNB to give me a limit increase but 4 weeks to rectify their mistakes!!! i have been calling up more than 5 times a week from the initial first complaint and seem to be getting nowhere. definitely will be moving onto another banker after this experience.