I am unable to sign into the correct Xbox account on my gaming laptop

Hi Microsoft Support,

I am unable to sign into the correct xbox account on my gaming laptop. I've only ever played on console, but finally bought a gaming laptop. I opened the xbox app and the only sign-in option was for an old account/gamertag that I created when I was young by accident and have barely ever used. I click, "Not you? Switch Accounts". Nothing happens.

When signed into the wrong account, and I click "Sign out", it just automatically signs me back in one second later. The only solution to this second problem I have found is to uninstall the app and reinstall. So I am basically stuck in a loop with an Xbox account I really wish I had never created. I'd love to delete the old one somehow. My current xbox account I've had for years and need to be able to use on my gaming laptop. I've spent hours searching online and in settings with no luck whatsoever. Please help!

:)