Additional to this, I and the others are already going out of our way to help. It makes our job easier when we do it on the forums, so that other people who have the same or similar questions can simply read the forums for answers.
This is how forums work.
So, unless you have a huge issue please don't abuse the system by using chat to get help. I will do what I can but others who come after you are disadvantaged by this and using the actual forum is far more desirable.
Sending me a chat message that seems like there's a real problem which I will chase via email and then asking for coding help via email is not on.
I could do this, but I would require you to pay me per hour for this service. The rate per hour would be exceptionally high because I simply do not want this happening. Easier for everyone if you simply start a thread and ask for help here.
I have a Kerv payment ring and it works in exactly the same way with NFC readers. If the door lock could read your old ring, it will be able to read the payement ring with no issues.
I was enjoying unlocking my phone with my payment ring until Google disabled the feature in Oreo, boo.
If your antenna + according circuit is matched at 13.56Mhz, there are no problem but I think it will be difficult to find an antenna that match with the according circuit currently on the keyduino and you will need to change some component value to improve your reading range ;)
Here's my reply from support at the end of Febuary
"We're in the final stages of refining production of the payment-enabled NFC Ring (and associated back end systems) at the moment. We're currently aiming to begin dispatch in the next couple of months."
I think you need to go back to the safe manufacturer to find out which chip it supports. You might even find it on the spec sheet of the product.
You need a sensor that will work with NTAG. In theory if it works with NTAG and is programable IE: accepts a scanned chip, then it should work. Perhaps find a shop that sell them and turn up with your ring, see if it reads it and can be programed to accept it.
There are lots of sensors and locks that are designed to work with MIFARE chips, which won't work with the NFC ring.
So just read up before you make a purchase.