I accidentally unregistered my Xbox from app. How do I re register it?

You may also want to try unregistering your Xbox from your account, then registering it again.

how do i do that?

I second this with a problem. I was directed here from support as well. I was sent the I Vite and downloaded the app but it says it is registered for another account t on the xbox when mine is the only one. Looking for any other way to fix the problem or
unregister my Xbox

No, I do not have the ability to report a problem. Again, I do not participate in the preview program. My console is unregistered, I do not receive preview updates, and I do not use the app. I simply keep it on the HDD in case I ever wish to re-register
for participation in the program.

I am just like everyone else, standard user with standard updates. The current "new" Xbox experience update is what I'm running with everyone else.

What i did for this was unregistered in the app but it takes time until this preview update wave is over and if you don't want to unregistered just try to get the people that you play with to get the update but it will take 48 hours for them to fully register
for the update i have done the same thing and it has worked so if not then try to get in contact with Microsoft support and they might be able to help you unregistered if you don't know how or you can wait and see if they fix the registering process and your
able to party once they release the update publicly.

I am wanting to unregister from the preview program, but the registration app only gives me the option to join. I know I am still registered since I am still getting the updates. Any advice on what I need to do?

Thanks