Hello, I have used the RTH quite a bit to empress others .  The last time i used it it was really scarry!!!  The Mavic did NOT RTH all it would do was climb to the limit of 380feet, drop a little and then climb again.  I did have trouble canceling the RTH !!  It would not stay on the screen??  Once it was canceled i had to fly it back to a really close distance for the RTH to work??  Can someone explain this to me with this little bit of information??

if you have done all your preflight checks correctly use the auto takeoff on the app and check the box precision take off it should take off and rise to about 5 metres when its done that fly as normal take it a fair distance and use the rth button

Yes all of this was done, Like i said this is the first time it has done this.  I just so happened to speak with another Mavic owner and he said he had a similar problem.  His mavic was flying away !!  could it be the update?   

This sounds like the well documented issue with the forward vision sensors.  When you initiate RTH and the path to the home point causes the Mavic to face towards the sun on the way home, it triggers object avoidance which causes the Mavic to gain altitude and try moving forward again.  As long as the Mavic is facing the sun this will continue until cancelled.  

Thank you, i will keep that in mind.  

Yes sensors flying directly into the sun can cause obstacle avoidance to kick in then Mavic tries to climb above obstacle, just cancel RTH and fly home manually in this case.

Off track is your first name David, I ask because I am a David Walker....

Yes it is !!!  Nice to meet another David Walker.  I am in Louisiana.

Thanks for the answers above. You can refer to their answers, if the drone is facing a strong light it will initiate obstacle avoidance, so it keeps climbing. And if you cancel RTH for the beginning, you can reactivate it for sure, on the RC or on left side of the app, but this is on the premise of enough power for the drone to do the RTH, or it will just land.