My new AirTag is not showing up in Find My app after battery replacement

I have a new air tag. It paired with my phone, but it is not showing that it is located in find my app where it belongs. It was to replace a dead battery. I decided to replace the existing Air Tag with a new one because I couldn’t close it after I placed the new battery inside. I have replaced the battery in this AirTag several times before but this time I couldn’t do that.

[Re-Titled by Moderator]