Created admin (me) and 2 users - admin is public, I can't create new user (me) under my email

I set up the WD My Cloud by following the setup guide. I made myself the admin, then set up my wife and daughter. When I then opened the network to back up my first files - I was only able to use either their user names or “public”, which I discovered was accessible to everyone in the house (not “the public”, however, it was not my own files - but public on our network. I then tried to establish my own user name - but, my email address is associated with the admin name - so I can’t set up my own user profile (except as a public profile) I get an error message that this email is already being used (um, yup, I get that - it’s mine…)
I’ve searched a few different ways for this - but to no avail. I am clearly doing something wrong but I can’t for the life of me determine how to have myself (the admin) not be public. I got the WD My Cloud to be able to back up our individual laptops, etc in our own accounts. If the admin can’t have their own private back up (yes, I understand it’s not “public”, but my own files are mine - not for everyone in the house) this unit is seriously flawed - Anyone have any idea how to work around this? I am simply looking to back up my own files - same as the rest of the fam…
Thanks - and apologies if this has been solved, but my searches here and online have not yielded any help.

Did you go into the Dashboard and turn off Public Access to your share? Then set each user with the access you want them to have. See example image below. Click on, tap or activate image to enlarge it.

Please read all the information provided and the Help information provided in the Dashboard.