Garanti Bank Changed My Loan Interest Rate After Approval

I applied for a loan through Garanti Bank's mobile banking system on July 27, 2025. The transaction was still running at a 2.79% interest rate, but my credit score was approved at 3.31%, which I accepted. With only the transfer to my account remaining, I logged in on July 28, 2025, to approve the transaction and transfer it to my account. Just as I was about to proceed with the transaction, I received a notification stating that the loan interest rate had been updated again, allowing me to continue at the current 5.15% rate. In response, I called customer service, and the person told me these rates were due to a weekend campaign. No one warned me about this, nor was it even mentioned in the contracts when I approved them. Do you think we're dealing with children? Should we be fighting your sly games amidst these financial difficulties? Please explain to us which law, book, or system accounts for the two interest rate changes, even though all transactions have been approved and the transfer to my account is still pending. Where exactly does customer satisfaction stand in this situation? Please address this and I look forward to hearing from you.