The maps in the Driver app may have difficulty loading for a few reasons:
1. Low cellular data coverage in the area
2. Location services are turned off
If you've experienced this issue, consider turning on location services for the Driver app in your device, and try driving to an area with better cellular data coverage.
If you continue to experience the issue, you can let us know by completing the "Anytime Feedback" form in the app. You can do so by tapping the question mark icon in the top right corner to the app to access the Help center, then selecting 'Feedback'. From there you can submit your feedback in the space provided.