bad service

MTN made a mistake of debit order and decided to block my line without allowing me to rectify the account now is over 3 months in arrears the line is blocked i checked with my bank at the agreed time of the debit the was money in the account i have arranged payment with them but they still refuse to open the line so i must pay debit orders every month without line being active. it look like they enjoy us paying without using the line. after 15 years of service with them