Can't edit shared notebook although I should have the rights

[ScarlettE. 0]

Hello, My father shared a notebook with me and gave me the highest rights level, so that I should be able to edit all the notes, but I can't. I can read it, but I'm not able to edit. It only works if he shares a single note with me. Is the function of sharing a whole notebook a premium/fee-based function? Thanks for your support in advance.