Angry mtn customer

I have a problem with Mtn since last year November 2022,being a loyal customer I was offers a laptop,that I will pay R169,but to my surprise I they debited R429 since January 2023,and I return the laptop within 7 days,I need you to sort this issue for me and I need my money back,because I don't have anything of them but yet they debit my money,and i have proof that i return theur laptop