My son was flying and out of the blue this happened.  Drone is only a few weeks old and the props were from a extremely reputable 3rd party.

Hi there. Thank you for reaching out and we're sorry for this unfortunate incident. I'm afraid that you may consider sending the unit in for proper diagnostics, you may request a repair service using this link https://www.dji.com/support/repair . Once you already fill in all the needed information, our team will contact you to provide further information on how to send the product to us. Thank you for your understanding and support.