keeps suspending my contract lines yet account is up to date

i am utterly disgusted in the level of service given to me by mtn , i have made payment of R1200 in June yet mtn cant pick it up and sort my problem out even though i sent proof of payment to ZAMA MAFUNDA JACOB RAMEETSE SIBONGILE ZULU and all of them have assured me my query has been resolved yet each month my account is suspended ,definitely not worth my unbroken decades of being a customer id rather take business elsewhere