Google Mail issues

Greetings, everyone.

Hopefully, I haven't wandered into the wrong corner of this forum. 😁

I've been a loyal Google user for ages, and frankly, it was always seamless.
Lately, however, my inbox keeps flagging an unread message that simply DOES NOT exist. It’s a ghost in the machine.

Does anyone have any insight into why this glitch is happening, or perhaps a fix?

Much appreciated.

Sort your emails by date and then check if any show up with a weird timestamp—something like 01/01/1970. If they're already sorted, maybe just look at the very oldest or newest messages to see if anything looks off.