the app doesn't work

IF you subscribed via adobe.com and not a mobile app store 

start here, https://helpx.adobe.com/manage-account/kb/stop-creative-cloud-trial-mode-after-purchase.html

ONLY IF YOUR ACCOUNT SHOWS A SUBSCRIPTION WITH NO PAYMENT PROBLEMS, proceed to these steps -

https://helpx.adobe.com/enterprise/kb/resolve-trial-and-license-expired-errors.html

and if that fails, https://helpx.adobe.com/download-install/kb/adobe-license-issues-keychain-credential-mgr.html

additionally, below are solutions some users reported:

if those all fail, change your cc language. eg, try international english

if that fails, change the install location

if you subscribed via a mobile app store, contact that store.

in the future, to find the best place to post your message, use the list here, https://community.adobe.com/

p.s. i don't think the adobe website, and forums in particular, are easy to navigate, so don't spend a lot of time searching that forum list. do your best and we'll move the post (like this one has already been moved) if it helps you get responses.

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