NFC not working - Trying to use Tags

I have a lot of Samsung Grand Primes we just got to use for my business. Is all we need it to do is scan NFC tags. The device has NFC capabilities and I have it on and cannot get it to scan tags or even use android beam. We have 65 devices and have tried this on 10 of them an cannot get it to work. Have factory reset and tried software updates as well. Greatly appreciated if anyone has any ideas!