Akbank Refuses to Increase My Axess University Credit Card Limit

I am an Akbank Axess University credit card user. I have tried to request a credit limit increase at least ten times, but I keep getting an error code through the bank’s app. Apparently, the limit increase can only be done via the app. When I contact customer service, they tell me there's nothing they can do and direct me to the branch. At the branch, I get different answers each time. I regularly use this card and pay my statement balance on time. I have been a customer of this bank for 2-3 years, yet I am unable to get my limit increased. I am frustrated and request that my credit limit increase be processed.