Hi,
Thank you for sharing your question. Hey, thanks for contacting me about verifying Microsoft Flight Simulator on Steam after you reset your email. I get that you're seeing a verification box that doesn't do anything, and I know that's super annoying when you just want to play.
From what I've seen on Microsoft Q&A, this usually happens because of email issues or problems with how your accounts are linked. Sometimes the verification email just doesn't show up, or the popup doesn't work because your new email isn't fully connected to your Xbox/Microsoft account.
Here are a couple things that usually fix it: First, double-check that the verification email actually made it to your inbox (and look in your spam/junk folders too). Then, try sending it again from Steam or in the game. Make sure your new email is really linked to your Microsoft/Xbox account. You might need to sign out and back into both Steam and your Xbox or Microsoft account, and maybe restart your PC before trying again.
I hope this helps.
Best Regards,
Noel