Loss of business

I have ongoing issues with my service with Vodacom. I am losing business because I don't have network most of the day. I need to restart my phone numerous times a day and then I have missed a lot of calls, e-mails etc. My work involves a lot of traveling and I need to get my calls wherever I am at that time. I have made numerous calls to Vodacom to sort this out for me and it just doesn't get done. I have also had my phone tested. I do not have any issues with other networks which seems it only points to your service being an issue. I no longer wish to be on contract as I am paying for services I don't get.