Lack of due care leads to ********** account in my name

After my contract ended in January, someone took the liberty of upgrading it without my knowledge, a **** license was used to upgrade the account and took an Iphone 11.

Since i found out I’ve reported to vodacom and was told to do an affidavit, 2 weeks later they tolf me they would close the account however this has not been done

This is affecting my credit record as it seems i am missing payments, I’ve been to vodacom stores no body could help me . I am extremely frustrated with their service