Vodacom Credit limit effected without my knowledge and no one can sort it out

<p>I switched one of my numbers to a top-up some months back and now my account keeps getting locked because of a credit limit which was not there before and no one advised a credit limit has been effected on my account. I've been sent from pillar to post by the call centre and accounts. This has been going on for over 3 months. I need this sorted as my paying my account for virtually no service. </p>