DSTV

I received a call in November 2020 regarding their price lock special, which I signed up for at R829.00 for 2 years. All went well until March 2021 when I was charged R968.00. After this the amount the following month came down to R 878.00 with no explanation. I have contacted the call centre 12 times over the past 2 months and each time I get given a reference number and told that someone from price lock will call me that same day. Unfortunately, I have not had one call back. What do I do next to get this problem resolved? 5 reference numbers are recorded below.