MTN SHOCKING SERVICE

Pay my account via EFT every month. On 2 June 2021 I EFT an amount of R3434.43. Ref I used was my old account nr was never told I had A new account nr and I have been with MTN since 1999!! Up until today MTN have never allocated that payment to credit my account. I am in arrears permanently despite me having sent proof of payment at least 20 times to different agents to have allocated and credited to my account. My credit rating has been damaged due to bad payer listing. My lines are constantly suspended due to the apparent arrears. I have my devices insured through MTN who now tell me I am not covered due to my account being in arrears the last 5 months so should something happen I will not be reimbursed but I still pay my insurance premium?? How fair is that?? Today I receive my new statements and my account is still in arrears as the payment for 2 June 2021 still not allocated so my lines will probably be cut off tomorrow - MTN are excellent at "loadshedding" - When they don't think a working device is needed by us!!! Cherry on the top I was told I have been handed over to the legal department due to my arrears!!! Shocking service and rude agents Who can assist me in getting this sorted out asap?