My NK 3A is dead, Nitrokey support is useless, what to do next?

My 3A NFC has been acting up recently. It isn’t the mini, though. This is a link to my issue. I am almost afraid to log out of certain accounts in order to test the NFC on my phone. I am not an “in-depth/super knowledgeable” user of this device and wouldn’t know when to “freak out” or not if I am permanently locking myself out of things. I have been slowly adding a 2nd key from a different maker as I run into this issue. It is the only way I feel confident trying to narrow this issue down on my own.