TV not working consistently

Could you provide more details?

Which set top box do you have?

Is it connected by ethernet or wifi?

When it isn't working, are you seeing an error or message of some kind on the screen?

Has anything changed in your home recently that would have affected the set top box, the router or the cables?

Do you have just the one set top box? If you have multiple, are all experiencing the same issue?

Have you rebooted all of your network hardware starting with the router first and then the set top box(es)?