Worst service ever

I have sent numerous emails and many numerous call but still no one has contacted me regard my query. my father passed away on the 11/08/2021 and i went in store on the 24/09/2021 to request his account be stopped and the telephone numbers be changed to pre paid. Anna from MTN Vaal Mall phoned me on the 8th stating she sent an email to complete my request but since the no one has contacted me. i have sent an email to Ncokokazi Nomlomo ref *** and still no reply. I am at my witts end i don't know what else to do and MTN just seems to not care as they can't even acknowledge my complaint.