Screen orientation screwed by iOS sharing

The app has portrait as default orientation. Using the app, nothing goes wrong and rotating the device does not affect the GUI and others.

Using AirDrop when sharing we first get the sharing window with the "More..." button.

If the user presses the "More..." button while holding the device flat, the whole app rotates. Doing the invert process totally screws the app. We are using Vuforia and the camera feed goes upside down before turning black.

The "More..." button calls for a new activity that seem to ask for the current rotation and (for some unknown reasons) also sends a message to the app about the new rotation. Can I prevent that?