What WD Device that uses OS5 do you own? Is this what a User gets or what you get? You should post this topic in the Community and the correct sub-forum for your device.
I have/my user have Samsung A42 5Gs that used to connect until I attempted to change the passwords.
My user is getting the message only.
As Admin for my 3T MyCloud, I am connected and have no difficulty using the OS5 to up/download files.
I have a similar problem after doing a 40 second reset I have no cloud access and when I go on the cloud website to log in I’m told there is no NAS associated with this account. I am using an WD My Cloud EX4100 and when going through the dashboard to either sign in or create an account I get the following