Change password on the NeXT chip?

Hi there!

I had the NeXT chip installed for about a month ago.
I’ve been playing around with it, changed door lock etc. Really fun!

The question I have is regarding changing the password on the chip. I noticed on the website it say’s that the default password is: “DNGR” and that it should be changed right after install.
I’ve tried using the “Dangerous NFC” app.
But when I type in a 4-digit password and scan my chip, it say’s: "Error: Lock Bits Already Altered’
It also say’s on the website that they recommend using the “NXP TagWriter” app to change the password.

Could someone who already tried this give me a guide on how I go forward with this?
It would be bad if I somehow lock the chip for good etc.
That’s why I don’t want to “just try it”

Is there also a safe way to wipe the chip back to stock?
Like delete all the info that I scanned into it?
F.ex. vCard etc.

The NeXT comes with the modifications that the dangerous app does, so you don’t have to mess with your chip yourself. And for wiping, really the easiest way is write a blank/meaningless NDEF record to it. These aren’t like hard drives where you can do forensics on it and get missing/deleted data back easily.

I see.
But the chip is set with a default password.
My question was, how do i change it?

I’m not sure about changing it, but you actually don’t need the password to write to it. The password just secures the lock bits which basically just keeps yourself from being an idiot. It’s relatively hard to brick an NFC tag compared to a T5577 FYI so don’t worry too much about it.