Worst Service Provider Ever!!

I got a data sim card contract with them last year. Asked them to debit on the last day of the month, but after the debit order, my account would be on arreas. I called them in October to enquire, they told me it's because the amount doesn't reflect immediately on their side. I asked them to debit on the 25th of the month, they didn't. I called them again, requestung for their banking details so I can do eft, they told me it would have to be done 10 days prior to month end for reflection purposes. I paid in December and January. I didn't have any problems. February, I paid on the 19th. On the 25th, they debited again. So I reversed the payment because I had already paid. I got messages that I haven't paid and the service will be interrupted. I called them AGAIN yesterday because I didn't understand why my service would be interrupted when I've paid. The lady that was helping me said it shows that my account is up to date, and I should ignore those messages. So, I recently received an email that my account is in arreas AGAIN. And it's messing with my credit record. Enough is enough. I can't call them again.