Received no bill now being charged late fees

I only receive bills from Edgars every second or third month

My last bill I received was 17 October 2017. I received no sms or notification that a payment was due, on an account that was R104.39. I didnt receive a bill for November at all. Received an sms saying that I have a payment due on the 7th of December, made a payment of R100, and received a new statement saying I have been charged a late payment fee. It says my account is now R154,04. So now all the sudden my account is almost R50 more than it was in October even though I didnt buy anything, and a payment was made.

I have now had enough of Edgars, because they blacklisted me in the past even though my account was paid in full, with no reason as to why it was done. I have now paid my account in full and would like Edgars to close my account once it reflects on their system!