air tags not working

I recently bought 2 air tags.

Everything seemed fine when I connected them. The next day I opened

up find my and there were no items listed and no way to access the

air tags. Now, my husband can go to the store 3 miles away and I

won't get a notice or he can be sitting in the next room and I get a

notice that his wallet is away. Did something go haywire in the

setup? How do I delete these 2 from my phone so I can re-install?

Thanks.