MTN is messing up my credit score and wont rectify it

I have been begging for two months for a paid up letter and no one responds. Shanah Ramasamy was quick to send me the banking details when it came to me paying my account but now that I need my letter its dead silence. Gugulethu Sihlabela acknowledged my paid up letter and sent a cute mail asking if they should close my account i said yes and asked for the letter and still no response. Now my account is handed over but no one communicated with me yet they have my contact info and email address. if you want to make this a legal thing then ill get my lawyers involved too. MTN is messing up my credit score and wont rectify it