Are you a Company Admin for the entire company?
Following the steps to ‘manage activations’ as admin doesn’t sign out the Members or endusers.
The assigned member(s?) should go to myaccount.trimble.com themselves and sign in with their individual Trimble ID.
After the procedure, sign out of SketchUp and ‘Exit SketchUp’ (eg. Make sure that SketchUp is closed)
If the user is performing the manage devices step and it’s still not working
Try resetting the sign in the state by deleting the login_session.dat file.
For Windows users the file is located in C:\Users*USERNAME*\AppData\Roaming\SketchUp\SketchUp VERSION\SketchUp
and no matter what their user name is, the right file will be highlighted if you use the Go to Folder… option in Finder’s Go menu.
Likewise, on Windows you can take this:
and paste it into the path field in File Explorer, and be taken to where login_session.dat is located, for the current user.
One interesting difference is that if you include the file name as well, Mac takes you to the document and highlights it in Finder. Windows actually opens the file, which wouldn’t do you much good with login_session.dat, especially as you’re there just to delete the file!