How do I proceed a refund request for a charge that should not have been authorized?

what's your account show, https://account.adobe.com 

This is a public forum, not Adobe support... other users can't help
Help Center https://helpx.adobe.com/support.html is a good place to start
A refund will take up to 14 days
To Cancel https://helpx.adobe.com/manage-account/using/cancel-subscription.html
-be sure to keep the verification email you will receive when you cancel
Log in and go here to check your account to determine your status https://account.adobe.com
You may only get a refund if you cancel and are charged during the first 14 days of starting a trial
Did you cancel everything?