Reinstalling Rocket League can fix some technical problems. You will need to uninstall, then redownload and install Rocket League.
To uninstall Rocket League:
- Select Settings
- Select Storage
- Select Games and apps
- Select Rocket League
- Select Delete
To re-download Rocket League:
- Select your local user account
- Go to Game Library
- Select Rocket League
- Select Download on the content screen