cancelling my Vodacom contract after 20 year

I ordered an online deal for my phone upgrade. Placed the order, got the usual message 'checking you qualify'. The order is never fulfilled, and the deals available now when I go back online are all more expensive/worse phones. I try to get an answer via online chat - they ignore me after I state the problem. The help line hung up on me. They really do not care about customer loyalty, obviously think that since I have been with them for 20 years that they can treat me however they want.