Lack of service / Service non-existent

I recently cancelled one of my lines with Vodacom to convert to prepaid on the 31.03. Vodacom disconnected my no in error instead of re-routing it to prepaid. I need to keep this particular no as have had it for years and is the only contact no I have. I have spoken to the call centre 3 times and have been into a Vodacom customer care centre and to date no-one from Vodacom has contacted me. Each time I have been promised that someone will contact me in this regard. Today is the 14.04,nearly 2 weeks later? I have been a loyal customer for many years and to date am still not able to use my phone. I find this service totally unacceptable and extremely poor to say the very least.