annulation d'une commande faite en double exemplaire

I've moved this from the Photoshop Elements forum to the Account, Payment, & Plan forum.

Please go to Adobe Customer Service (Make sure to sign in to your Adobe account first and allow popups and cookies on your browser. You may not be able to see the chat window if using a VPN.):
https://helpx.adobe.com/contact.html?rghtup=autoOpen will automatically open the chat window.
Type "Agent" in the chat box to bypass the chatbot and be connected to a person.

or Twitter:
https://twitter.com/AdobeCare

Bonjour.  This is a user-to-user forum.  So we cannot help you with purchase issues.  Try contacting Elements support. You can start a chat session by clicking on the blue Contact Us button under the Help & Support menu at Adobe.com. Hours of operation outside of the United States are limited.

You activate Photoshop Elements when you first launch the Editor.  You will be asked to sign into your Adobe.com account and will then be given a screen to license the software.  Elements does not show activated devices in your account.  You are allowed to activate the license on two machines, but you can only use one at a time.

If you purchased from Adobe, there should be no problem getting your refund.   There is usually a 30 day money back guarantee.