Contacting Riot Games Support is really simple, just follow these simple steps:
- Go to this page: https://help.steampowered.com/en/
- Click on "Games, Software, etc."

- Search for the game You have issue with

- Pick "It's not in my library"

- If You are not logged in, You will need to login now

- Click "Contact Steam Support"

- Fill Your request with all necessary informations and screenshots and click "Send"

- And that's it!
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