Dstv disappointment

I bought a Dstv explorer from my sister a new decoder. We started to use it in February this year. In May the decoder started to give us problem. I went to Dstv Agency in Thornview Soshanguve. That is when they to me to come back after 60 days the decoder is still new. I went back in July they told us to come back in August after the 15th. When I called multichoice head office they told me to go back to the Agency to replace my decoder. Yesterday they told my husband to buy new decoder. Today I went they told me that I came late I was supposed to come before the 3rd of August to replace it. I am so disappointed about this to think that I have been using dstv for more than 10 yrs today I wish I can live it. I will leave it for Internet.