Adding Shared User But Comes Up As Owner?

I'm trying to add my wife as a shared user to our Ring Doorbell 2. Problem is that due to the fact I've lost my speech to a (slow form of) ALS we initially set her up as the owner years ago. However, because she hates technical stuff (she's 70) we soon changed it to me as owner not long later. Now when I try to add her as a shared user she gets the email and logs in but it still says she's an Owner and as such wants her to add a device including scanning QR code instead of just granting her access to "my" Ring video doorbell. How do we resolve this please? To complicate matters she uses an iPhone which I can't drive so I'm trying to communicate to her what to do. TIA Gary