Your device may not be able to run the app. Make sure you have an ARKit (iOS) or ARCore (Android) supported device.
Minimum specifications for iOS and Android:
Apple devices running iOS 11.3 and above: iPhone SE and above and iPad 5th Gen. and above.
Android devices running Android 7.0 and supporting Google's ARCore v1.7 or higher.

If it isn't a compatibility issue please get in touch with our support team on with details about the problem you're experiencing and we'll do our best to help you!