I was having some unexpected tech problems with my 2018 Roku Ultra. One of my dogs walked over the remote (the dog and the remote were on the bed together) and somehow confused the device by pressing most to all of the buttons at once. There was nothing here on these forums in dealing with this particular problem. And of course there is no customer service anymore anyway. Here is what I did in a nutshell:
I first did a simple "warm" reboot (by shutting off the device and pulling the electric cord out of the wall socket for at least 30 seconds) to it to clear the cobwebs (the router and smartphones always did respond to this method when they sometimes get a bit glitchy). Did not work this time. Then I went to the final major-desperate-fix and did a complete Factory Reset to my device. This option is so drastic that you have to type a 4 digit number before it performs this operation. Still, it worked did like a charm. Not only cleaned out the still unknown cause of my Ultra's failure (the inner workings-not the dog), but I was able to update everything else might have missed on that device for awhile at least. The device is now working better than before the complete reset.
Treat your device like the sensitive "computer" it is and generally it does the trick!
And remember to keep the remote and the dogs completely separate from each other! (This applies to the odd cat, small child, and clumsy partner, too).
Mine won't be giving me anymore trouble either! I'm replacing them all with Firesticks since NOTHING suggested works to alleviate the constant recurring random disconnection from my wifi while everything else in my home stays connected. I've tried every suggested "fix" and they still disconnect whenever they seem like they want to. Tired of it, and tired of ROKU seeming to have no interest in fixing the problem instead of just offering temporary bandaids to cover it up for a little while
I am doing the same thing. No one can seem to explain the loss of my feed, disconnected devices an the inability to download the apps all over again without putting in a chip.