In case you need to change the account (For example if you linked the wrong one), you should unlink the first one and follow the steps above again! Follow these steps to unlink your account:
- Go to twitch, click on your profile name in the top right corner
- Select settings
- Go to the connections tab
- Navigate to where you can see the link between your twitch account and Rocket league
- Click on Disconnect.
- Repeat the linking procedure with the correct account.