[AC Question]

I am using some old credit cards (not valid anymore) as NFC tags to trigger events on my phones. Lately I find that two of them can read the cards and other two cant.
My phones are two S3 running 4.3 and 4.4.2, these can read the credit cards like they always did, one Core LTE (sg386) running 4.4.2 which used to read the cards and now doesn't react to it at all and an S6 running 5.1.1 which I just started using at work and also cant read the cards.

Anyone has a plausible explanation about why suddenly the credit cards cant be read? On the S6 I just presume they decided to limit the capability of the phone NFC (possible?) but I can't understand whats wrong with the CoreLTE since it always used to read them and now it can't (only credit cards, I thought it could be hardware related and I tried other NFC tags and my bank card and it reads those just fine).

I noticed this behaviour after downloading Trigger on the CoreLTE but I'm not sure that could be at fault since I didnt use that particular phone to read the cards in some time and I read that some updates can be the cause of the problem. However those phones didnt receive updates in quite some time and if its the updates, I cant understand why the S3 running the same android version keeps reading every tag, credit card or not, like it always used to.