First thing to do is find someone with an android (you must know someone) and use the android DT app to protect your xNT before you go writing to it.
Second, it’s probably not working because either you have swelling (increases distance between tag and reader) or most likely just aren’t placing the phone in the proper position and orientation in relation to the tag for it to get good coupling. To get a read with the xNT on almost any reader, it is critical that you understand exactly where the antenna loop is on the reader and orient the tag perpendicular to it.
I don’t have an iPhone so I’m limited on what I can tell you. On Android, Taginfo will recognize a tag whether its got data on it or not. I would imagine the iPhone is the same.
“An iPhone NFC app only has access to the NDEF records; apps do not have access to the NFC chip’s UID or other special features in the NFC chip.”
Well I guess it sounds like you might be right…(though I have no experience with the iPhone) And you can;t write tags with the iPhone so you will HAVE to get some sort of other reader/writer to do anything with your xNT. Sorry. I suggest dumping all your apple products. hahah
I don’t know how to write on Tags with an macbook - but you can buy the Dangerous Things KBR USB Reader to login into your macbook - you don’t need to type your password - this works perfect.
I have a macbook air and a Samsung Galaxy S8+ - it is also possible to transfer data between the phone and the macbook.
Try to get an cheap android phone with NFC.
For me it was the first time hard changing from an iPhone to an Android Phone - but now I love it.