Mtn block client cellphone number for delayed contract payment. Very Unfair

Mtn has not only let disappointed me but i feel so betrayed and i took a contract with them 2january 2022 and for 18months they recieved all their payments through debit order without fail unti i started having financial challenges i skipped july payment and instantly they blocked my number from making calls or use data and airtime which I'm still billed for and for 3months i couldn't use airtime or data on my contract yet i was billed and paid for it anyway

I made catch up payments in september and in october they completely blocked my number i approched mtn store only to be told u havent paid so we blocked your number and was forced to make upfront payment so they can unblock it.

My question is, is it even legal to block a client's number because they are owing R1200 on an ongoing contract? If you block my number knowing very well that I'm a self employed entrepreneur because its well stipulated on the contract form i signed, how do you expect me to earn a living,? how then do you even expect me to pay what I'm m owing you, let alone the rest of the contract without income? I also wish to know if i managed to make payment, will mtn compensate me for the loss of work and income i suffered while they blocked my number? I believe if you owe a giant company like mtn in this digital world, there are so many ways they could deal with your debt than block your entire livelihood by blocking your cell number as if by blocking it hey will cancel my debt, im still paying for it anyway