Call centre agent hangs up on you

I am trying to upgrade my package as it is expiring. It is a nightmare going through the call centre that bounces you from one agent to the next. When you finally get through they contradict themselves. The packages they offer are significantly worse than previous years, despite data becoming cheaper. When I asked the agent the different options to get a decent package he gave me options that were just more expensive and not including the features I asked for. When I asked for more options he got frustrated and hung up. He didn't give me his name, so he knew I wouldn't be able to report him. How convenient. No reference number either. Now I need to spend another hour bouncing from one call centre option to the next before finding someone who can start the whole process from scratch again. Why does Vodacom make it so incredibly difficult and frustrating to use their services?