No Call back as promised

I have a duel view premium package with Multichoice. I have had a problem with my second decoder for the past 2 weeks where it shows an error code E143-4. I called in several times yesterday from my cell phone using all my air time and was promised on these occasions that the Technical department would call me back. Trevor told me they would call me back at 18h30pm and when no one called back, i called in again spending another 20 min on the phone having to explain the error code all over again but this time to another guy. While on the phone with him the 2nd decoder decided to work so i was finally happy but that was short lived. It stopped again and once again i had to call in and this time spoke to Angela. She assured me that a Technician would call me with in the hour. That was at 21h00pm. I am still waiting! I am paying over R800 a month for what? POOR SERVICE, that's what. Can anyone please explain to me why my duel decoder is NOT working? I also cannot watch the HD channels and was told that my spliter box is not strong enough to receive the signal for this. Is this possible? PLEASE HELP AS THIS IS VERY FRUSTRATING!!!!