Reinstalling Rocket League can fix some problems. You will first need to uninstall, then redownload and install Rocket League again. This will not delete game save data.
To uninstall Rocket League
- Press the Xbox button on the controller
- Select the Profile & system menu
- Select Settings
- Select System
- Select Storage
- Select Internal
- Select Uninstall
- Select Rocket League
- Press Remove selected
To re-download Rocket League
- Press the Guide button on your controller
- Select Xbox Home
- Select Settings
- Select Account
- Select Download History
- Select Rocket League
- Select Download Again