Vodacom service is beyond poor

Vodacom without my permission and specifically against my instruction converted by account to a prepaid account. I am overseas and wished not to continue with my contract that expired in April Going now through the helpline is a nightmare as I am now a prepaid customer! What the hell! It is a disgrace they cannot follow a simple instruction. My wife also has exactly the same problem. They are worse than Telkom and the SABC