Be sure that you are signed in and have activated the software—i.e., ensure that you are not running After Effects in free trial mode. The update will not work if you are running the application in trial mode. Sign in to Creative Cloud using any Adobe Creative Cloud application on your computer to activate all Adobe Creative Cloud applications on that computer.
If you’re not using a trial version, but you’re seeing the message that the update is not applicable, try one of these tips to force the application to be recognized as activated: Sign out of and then back in to Creative Cloud to refresh the activation state. Also, launching the After Effects render engine (not the full After Effects application) can refresh the activation; the render engine doesn’t have the crashing problem that the full unpatched application does.
more details here: