Not usually but sometimes they just stop working. If you know your pet has a chip and no reader can find it go to your vet and talk to them about maybe chipping the pet again. My cat that passed away had 2 chips when I got her from a rescue. Only 1 chip was active. We could see both chips in her xrays. Talk to your vet.
It does not expire, it may not work well
It is better to ask or investigate to know what to do.
No they don't expire
Do not believe so. I'm not the one to ask questions . Speak to someone that works in there.
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