Nu Debt Management dragging my name down without proper investigation

I've been harassed by this company for adding my name to the debt review when I don't know anything and They've sent an email to the wrong person.

From: Collections @nudebt.co.za 6 December 2023 Good day, NJABULO MHLUNGU, Our reference number: ND***1 We act on behalf of MTN, hereinafter referred to as our client. You are currently indebted to our client for services rendered to you. No record of payment has been received on your abovementioned account and it is our instructions to claim from you, as we hereby do immediate payment in the amount of R5428.89.

I'm not even related to this and they keep on sending it to me. Get the details of NJABULO MHLUNGU, Our reference number: ND***1 and STOP HARASSING ME