DSTV Decoders 3A do not work, even when we replace it still does NOT work

Our decoder through last month and this month has been changed seven times because it never wants to work as it should, we are tired going to the dstv customer service to change the decoder continously. It's a disgrace because dstv seems to not having a proper dstv decoder unit that should work correctly. This is a disgrace and bad service and it's getting worse. We replace our LNB (which was expensive), but still it states either upgrade now which we do but it does not upgrade in three hours it still wants to upgrade. We will consider cancelling with dstv as it not at all coming to be user friendly, the money we paying per month it's not working at all for the money we pay on premium for the month.