Trying to use TeamViewer with someone and need to enter an admin password but it shows a blank blue

So I sent a computer to someone out of state but made myself an adminstrator before I shipped it. They are wanting to install a printer but it requires the admin password to allow it. When I tried using Teamviewer to install it, it does not show me a place to enter the password. However, the person on the other end see's the spot to enter the password. Then, I tried to switch accounts to my administrator account. The other person can see where to enter the password but my screen shows up as a completely blank, blue screen. Any tips on how I can allow this install without needing the computer to be shipped back to me? Thanks in advance!