Do you use an App Password? If so, try a new App Password. Sometimes, changes (i.e. updates) are made to the iPhone, and then mail server syncing becomes an issue (which is what a new App Password it intended to fix). Go here for gmail: Sign in with App Passwords - Google Account Help - Google
I turned on archive to run every 180 days .
It MOVES email from gmail to the archive folder and removes them from the gmail server (imap )
I do not use local folders only archive so I have no experience on what archive does to local folders.
However Gmail is sneaky you may have to go on Gmail to the ALL MAIL folder and manually remove the archived items. Gmail wants you to use up space so they can charge you. Unless this changed recently
There is are no Thunderbird accounts. Email accounts come from email providers.Thunderbird is software on your computer and Mozilla has no control over it.Who did the message come from? Looks like gmail from the address you posted. Ask them.
If your laptop or smartphone was stolen, you can use a service like Gmail or Dropbox to find the IP address of your thief. When you log into those services from any computer, it logs the IP address used, and displays your last used IP in your account. In Gmail, it's in the bottom right-hand corner under "Details," and in Dropbox, it's in Settings > Security under the details of each individual computer. If the thief used your computer, the last logged IP address may be theirs instead of yours. Again, though, if they're smart, they didn't use your computer and this trick won't work.
We can't stress this enough: the best way to avoid this situation is to take precautions ahead of time: install software like Prey, LoJack for Laptops, or Find My iPhone. Keep your gear with you at all times. Make sure your doors are locked. The best way to keep your laptop in your hands is to prevent it from falling into others' in the first place. After someone steals it, you're riding on luck.
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