G'day. At my office the doors are locked with an NFC reader. We carry around a little NFC tag on our key chains which will read out a number and this then will open the door if the number matches a number in the database. I am tired of carrying around the tag, people keep loosing it, forgetting it and it would be nice to open the door using a Phone - which we tend to always have on us. So I used a credit card which is NFC enabled to readout the NFC information, added this number to the database and can now open doors using my credit card. This is pretty cool. If I forget my keys (most likely they will be on the desk but silly me left the desk without them), I may have my wallet with me. Then I tried Wallet.app on my iPhone and select the same credit card. However the door doesn't open. When looking in the door software I noticed that the tags will always transmit the same number. So does my credit card. However Wallet.app will read out 4 readings (or maybe just one very long one) and they are always different