Installed Unity Hub on my PC with an existing Unity version installed 2017.3.1p1, Unity Hub asked for a license key (have one use PC and one on Mac), so I revoked my license on the already installed version and then added it into Hub. However Hub won't launch any Unity versions and when I try to put the key back into Unity 2017 it won't take it (Key already used). I have a Unity support ticket on it (#472186), which I submitted on Saturday at 1AM and still have heard nothing back on it (Tuesday 3PM EST). I really need that serial key to be usable to push out updates on Steam without Unity Splash Screen. Would love if someone at Unity could help me out with this.