MTN home router contract

I got my router and it worked on the first day second day it lost connectivity I called them and they told me about location change so they turned it off which they didn’t explain when I was taking the contract and I live in the rural area it was connected in town at the MTN branch it never worked again I told them that it is not working and I want to cancel it they said they can’t do anything about that how can I pay for a service that I haven’t even used and now their router is here useless not even working and they have the audacity to dent my credit record for something I haven’t even used please help this is draining me I have worked so hard for my credit record for them to dent it I regret ever speaking to them