To authenticate, your phone has to be 'at home.'
Try to make sure your phone's on your home network exclusively when attempting again, but this can be trickier than it seems.
Your home also has to be set, I know this is odd, but make sure your set top box is powered on, but if it's already on, power cycle it so that it has a fresh 'home.'
Additionally, many modern phones have a 'wifi assist' feature that turns data on when it finds the wifi to be inadequate. The measuring done on these features is very arbitrary, meaning it can actually be hard to tell sometimes.
Disable data, but also disable wifi assist on your phone, and then try again.
Here's how to do it on ios;
and here's how to do it on a lot of android devices;
Wait my above post I wrote, I thought you were getting that error on PikTV on your phone.
If this is just about your wifi;
- Make sure MAC filtering isn't enabled on your router
- Power off your phone (not sleep but physically power it off) and then power it back on.
- Make sure your router firmware is up to date and also if that still doesn't fix it...
- Factory reset your router.