Since you mentioned using your nail, I’m guessing you're trying to press on it to initiate pairing or reset it ... correct?
Some things you can check/try:
- The AirTag's battery lasts approximately for one year with normal use. Your five-year old tag may have a worn-out battery. Try replacing the battery with a new CR2032 coin cell battery (make sure it’s one without a bitter coating, as this can prevent proper contact). After replacing, you should hear a chime indicating the AirTag is powering up. If that worked, go on to the next item.
- Try resetting the tag:Reset the AirTag: How to reset your AirTag - Apple Support. If that worked go on to the last item.
- Try pairing the tag again. I suggest doing so with your iPad first. If that doesn't work, then try with your iPhone. Pairing associates the tag with your Apple Account (aka, Apple ID). Ref: Add an AirTag in Find My on iPhone - Apple Support
If it still doesn’t work, then the AirTag may have sustained water damage or other hardware issues over time.
