Communication failure

I have an account with telkom mobile, in december I got paid early and called telkom mobile and asked if they can make an early deduction because we got paid early then they advised me to make a manual payment of which they provided the details. So I did, but on the 31st of december they deducted after I have already payed manually. I called and queried tje transaction they apologised and said I can go to my bank and have the funds reversed (mind you, a reversal is costly) so I did because I needed the money. So last month they did not deducted and failed to communicate as to why so sunday the 11th of February I called to query if they are going to debit their money this money or not because last month they did not. I was told that my line will be cut off if I dont make an immediate payment within 48hrs of which I fail to understand because they never made an communication with me as to why they didn't debit their money but now they're telling me they will cut my line and list me on credit bureau. This is very unfair on my side because its not I dont want to pay but I just dont have the money now.