Recieving Overdue Etoll - NEVER BEEN BILLED

I just got an sms for an overdue e-toll fee and now in debt collection process. VERY Interesting since I have not been to Johannesburg or around in more than 3 years. So where you suck this out is absolute Bull ****... I HAVE NOT ONCE RECEIVED A BILL, So must i magically come up with a number or do you do that?? The sms contains NO REFERENCE number and no mention of what I owe.

IS this just complete incompetence or a completely *********** system that does not work??