Assignment fails for TeamViewer Host on Raspberry Pi 3

Hi,

I would like to set up TeamViewer Host on my Raspberry Pi 3 in order to control it remotely. I have already successfully installed and started the application on my Pi. Now I wanted to assign this installation to my account, which however is not possible.
As you can see on the screenshot even after having entered my user credentials the "Assign" button stays grayed out and inactive.
Does anyone of you know or have an idea why this could the case and might give me a hint how to solve it?

Thanks and best,

Cristobal