DOWNLOADS DON'T WORK

I repeatedly experience failure when I attempt to watch a download. I have contacted the call centre a number of times and e-mailed for support. They do not know what the error message that appears means and definitely do not have a solution to the problem. Re-installing the app doesn't help. It is much easier to download from DSTV or Netflix or YouTube. Its no use having a great selection but the download function doesn't work