Unfair blacklisting, bad service

Last year 2022, September, I was called by Mondo on behalf of MTN and they offered me a router and I took it. That router was operational only for that month which is September. From October until December I was unable to use it, it just connected without internet so I visited MTN store in Rustenburg Mall, they told me that number doesn`t belong to me. they gave me a Mondo email address since they were unable to assist. I ended up disputing their debit for the month of December because they were not helping but busy earning interest from my hard earned money. Up to date I haven`t got assisted but I`m blacklisted for a service I never got, I`ve been reaching out but they just putting me on hold. I`m losing out on job opportunities bacause of this issue. I apparently owe MTN R5000+ which I have no idea is for.

MTN is denying me life opportunities!!!