Very bad service from Dstv

I am sending this on behalf of my sister whom i live with,she recently app**** for the DSTV Explora ultra package with a price lock offer of R549/m for 24months.The decoder was installed on the 22nd of June and was advised that multichoice need to deliver the extra decoder which never happened.She has been escalating this matter to DSTV since June and still no answer as to where the extra decoder is,according to them it was delivered on the 15th of June,which she requested a POD for and they never sent it they only told her it was signed for by Chris,who we don't know as we don't have such person in our household.This is seriously ridiculous,now since June the amounts debited from her account is not for the package she app**** for,June installment was R774.94,July installment R646.85 and August installment R832.00,where is the price lock for 24months she app**** for.They need to explain where the extra decoder has been installed/activated as it was definitely not installed/activated at our house..We need this matter to be sorted as quickly as possible..Because this matter has been escalated since June and still no positive outcome...