Mtn ****med me

I have been with MTN since 2021.But when I was my time to upgrade my contract, they did not allow me to me. they continued to take my money, when I tried to cancel the contract they kept delaying me up to the point that even when I finally went through with the cancelation they continued to take my money and they denied that I have ever called them.Even the reference number that was given to me was denied they told me it's a 2024 reference number.