Telkom absurd billing bending

I have 5 FIXED mobile contracts with Telkom. I am paying my bill every month by debit order. These contracts are almost 2 and a half years old, never EVER skipped 1 single payment, and get debited by their calculated amount. NOW, ALL OF A SUDDEN, I GOT SUSPENDED,( PAID UP TO DATE ACCORDING TO THEIR BILL) NEARING MY CREDIT LIMIT THRESHOLD OF R4500 (aparently 80%). Now they want me to pay 2 installments this month (R3600 per month!) SO HOW THE HELL ARE YOU ABLE TO CREEP CLOSER TO A CREDIT LIMIT WITH FIXED AMOUNT CONTRACTS, REGULAR PAID DEBIT ORDERS CALCULATED BY TELKOM THEMSELVES, PAYMENT DATES SET BY TELKOM ETC. THIS IS ABSURD TO TELL A CUSTOMER AFTER ALMOST 3 YEARS TO SUDDENLY PAY A DOUBLE PREMIUM OUT OF THE BLUE WITHOUT ANY PROPER EXPLANATION. THIS IS ******ION, HORRIBLE BUSINESS PRACTICE AND BLATANT PATHETIC HORRIBLE SERVICE. I NEED MY LINES RECONNECTED SINCE IM NOT IN DEFAULT!!!!!!!!