New roku device and it won't let me even do the internet set up before it flashes the screen and starts over. The 2 I had last year did the same thing, so that's why I am trying this new roku le
The first thing to try is an alternate Internet connection. The easiest thing to try is a phone hotspot. For some users, this has allowed completing setup and then had no issues connecting to their home network.
But it's always possible that the device is defective. I had an Insignia Roku TV that was stuck on the update in a constant loop. I returned it to Best Buy and picked up another, and it's worked fine for close to 7 years. Sometimes electronic devices simply fail for no known reason.
@WendyJ1, if you have it plugged into your TV's USB port try using the supplied power adapter (assuming there was one).