No feedback. No response. No signal

All started this week Monday 10 August 2015. My tablet went on the blink. Cannot be used. Then my phone, same day. I am able to use data intermittently. However, I can't make calls, I can't recieve calls. The voice messages being left, I can't retrieve. I can't call 808. *141# is not working on either my phone or tablet. I get a message on my tablet saying my monthly data bundle has been recharged, what use is this if I can't get it to work? I called 808 from a friends number, I was pushed from pillar to post between call centre and the coverage technical departments. Neither knew what to do. I've expressed myself on twitter. @bravothreezer0. I have been completely ignored. My phone miraculously worked today, Friday 14 August 2015 for about 2 hours and now, it's not working again. I am at my wits end. My phone bill every month actually reflects a few people's rent bills. I pay good money, and all I get in return is lousy service. I actually shudder to think how much business I've lost because my clients can't get ahold of me and move onto someone else. However compensation from MTN would be impossible. I'm very disappointed. I need this resolved as a matter of urgency!