Whom to contact ?
Same here with PS CC and PS CS6.
I have tried via Adobe chat 2 times and they keep asking me to try later.
There is a magazine deadline and I must finish with retouching but I won't be able because I made a mistake and joined to Creative Cloud and now even my PS CS6 does not work.
No use buying the CC then.
What to do now ?
Stop subscription and move to the pirated editions ?
One of the Adobe guys told me a temporary solution until they fix this problem.
Uninstall everything Adobe incl Creative Cloud manager, create a new account with different email, download Creative Cloud manager, sign in with your new account, download trial version of any software.
It works but hopefully I will be able to switch back to my original account what I have been paying for...
You might try these, check if it helps.
Deactivate one of the previous machines before proceeding. If you have access to the previously activated machines, choose Help > Deactivate within the application. Alternatively, you can deactivate all previous machines by following the steps below.
1) Launch the Adobe product.
2) At the Maximum Activations Exceeded screen, click Continue.
3) On the Sign In Required screen, click Sign
4) Enter your Adobe ID associated with your membership and click Sign In.
You can also refer to : http://helpx.adobe.com/x-productkb/policy-pricing/error-maxium-acitvat ion-exceeded.html
You can contact Adobe Technical Support via http://adobe.ly/yxj0t6