The internet ethernet port for the dome is the one closest to the DC power cable.
It does have a slightly different icon (of a world).
Are you replacing an old Koala-safe? if so you need to un-pair the old one.
If your app has un-pair, then you can doi it yourself - otherwise email support telling them the email address used for your account, the old and new mac addresses and tell them that you are changing from an old unit to a new dome.
They should be able to un-pair your old one and then allow you to pair the new one.