Part 107 UAS pilot reported a partial loss of control of the UAS resulting in a fly away. The UAS pilot was able to command the UAS into the ground to prevent it from flying further away.

Narrative

I was flying a DJI Mavic 3 with the DJI RC Pro controller. After going around site and completing my photo run; I started my video. Did one loop around the property and starting my second video run when I noticed my view was off on the drone screen. When I stopped to reset the view; I noticed the drone push to the left position at a high rate. As it was going away from me; without input from me; I noticed I still had yaw movement and altitude control. Right stick; mode 2 was not responding. I turned the drone to flyover head as I tried a RTH procedure. It came close to me; lowered to about 20' and the RTH stopped and now the drone was flying in the direction of the airport. The drone was traveling at over 20mph and I felt the safest thing to do was to slam it into a dirt pile on site to stop this runaway.I have all files from the controller and drone and it was sent to DJI for inspection and fix. It was determined that the controller right stick got stuck in the left push direction and full speed. They replaced both items for only $XXX.Looking back; switching to cine mode would of slowed everything down and would of allowed more time to process and work through although the ending might of been the same. No injuries; no one even saw it occurring. I never knew this could happen so great lesson for me. Just wanted to share in case you are tracking. Thank you.