Error code 721

Once or twice a week our HD channels go out and we get an error code 721 saying we haven't purchased the channel, I would call DirecTV and spend 20 minutes on a call just for them to send me a signal.  When they asked if there was anything else they could do, I said make my tv stop going out or let me reset it myself, which I learned you can go online and do in much less than 20 minutes and it works.

Now I just want to figure out how to make it stop!! It happens just about every Friday night and it is annoying.  Does anyone else have this issue?  At one point they escalated it to an engineer and it stopped for 3 or 4 months but now it is back and it has supposedly been escalated again but hearing crickets....