Vodacom Failed Me

I called Vodacom customer care line regarding the problem that I have with my Internet every day after 5:00 I some how struggle to connect to the Internet and that is the time i need to use VPN connection to do maintenance on my work Servers, the next day I had to explain to my Boss why didn't I do what I was supposed to do which was difficult for him to believe me that i could connect to the internet because I always get 5Gig of data every month and by that time I still had 6.7 Gigs of data all people I spoke to told me they can't see anything wrong but yet I still couldn't connect to the internet all they know is to tell me to restart my Tablet which I told them I did 7-8 times and took out my sim card 3 times. I got another sim card because one of the agent's told me it might be the sim card but I still experience the same problem and I even tried to put the sim card to my cellphone and it still didn't want to connect. I have installed IP TOOLS software on my Tablet and I noticed that when I lose connection I loose ip address, subnet mask, dns, server address and my internal ip address change to something else. Up until now my problem hasn't been resolved.