Bad service

So we didn't pay and was cut off for like 3 months, we paid the R1000 and something and we were reconnected, later told to pay more we paid today we get home we are told we owe R822. Now we told to send proof of payment. We never had to keep them before. If I use my ID number surely that's my reference which is what I have always used before. If I was reconnected it means the payment reflected.