Well, I didn't start a new thread because this is the AirTag that I bought to track my car, but I do see your reasoning (now) for this to become its own thread. This AirTag was bought from the Apple website and shipped from China, it took forever btw. We bought another one from Walmart locally and it's worked perfectly.
This problematic AirTag seems to work fine except for when I leave it at the house, that's when the time and date never update when I leave with my phone. My phone just stays on "last seen" and whatever time that I left and shows the location as my house. Also, once I get home, then it will update, even the find green arrow will bring me to it.
My friend bought a pack from Amazon and they've all worked too. This particular one from Apple/China is the only one that I've had problems with it. If I can't figure it out with GUI/software soon then I'll try the battery reset that you suggested to me.
No, the other devices are not my Apple ID, they're all my family members and all purchased by me. Some of them, the older devices, were mine with my Apple ID at once but now they're in their own Apple ID of the family member(s).