"This note is not an AnkiHub note." error when I try to protect fields in a specific note

Hello. I am trying to follow the “Special Tags for protecting fields” section of the documentation to protect individual notes (by right-clicking in the card browser and clicking “Ankihub: Protect fields”). However, even for cards that definitely are AnkiHub notes, I am getting the following error:
image

For context, I originally protected the entire “Text” and “Extra” fields in my AnKingOverhaul notes so I can make personal edits. Now I want to add special tags to protect the fields of my active notes so I can uncheck protection for the “Text” and “Extra” fields and thereby allow them to be overwritten. My goal is to only protect the notes I have unsuspended from AnKing already—some of which contain personal edits—so that I can continue to receive updates for any currently suspended notes that I may unsuspend in the future.

How can I resolve this error? Also, is there a way I can mass protect the fields of thousands of notes at once? Thanks so much in advance.

I was able to resolve my issue! Thanks to anybody who took the time to read my post.