Line suspended for wrong reason

We were charged for our old line and new line after we had moved provinces in February! The over charged amount had been on our bill for 7 months! My husband had been on their case for months trying to solve it! We<br> pay our new line bill every month except the amount over charged, hoping it would be rectified! Today our <br> account was suspended because the over charged amount has not been paid! Is that fair? No warning our lines are going to be cut! How do we sort it out? No one seems to be able to help us at Telkom! Though a Lindalwa did try her best and was very polite this morning!