Billing becomes a nightmare

For the last couple of months I paid a visit to Mogale Cty on a regular basis trying to sort out these accounts which reflects no payment. Every time I am promised that it will never happen again as they changed from one system to another. Every time I need to go and fetch proof of the payments made as their fax number is out of order. Then they have the cheek to add interest on the \outstanding"money. Must we"