How can I keep another iPhone from picking up MY AirTag?
How to keep another iPhone from picking up MY air tag?
[Re-Titled by Moderator]
AirTag
Question marked as
You can't. That is the way they are designed to work. It's a safety feature to thwart tracking/stalking people.
The only means is to remove the battery from the tag, which will, of course, render it useless.