Afetr 3 days of calling, nobody can help still

I took a phone on contract in December from MTN Mall of Africa branch and I was told the first debit order will go off by end of January, it never did, so I called and they said I should wait for February, now before the month(February) ends they send me an sms saying my account is overdue and I need to go and make a deposit at the bank, nobody called to tell me whether the debit order can not go off and the fault is on my side/my bank. I have 3 days calling them but still I can't get help, apparently there is no debit order setup for me, even though I gave them all my banking details.