I was flying a mission (with Phantom 4RTK, Remote controller: GL300N, & D-RTK 2) that required LAANC approval according to: Kitty Hawk & AirMap it DID need approval; but on DJI fly safe it showed that it was NOT in any controlled airspace. I launched my drone up in the air, to start a 2D mission, but it just hovered at the starting point and wouldn't take off for the mission.  I brought it back, got on a computer and did a unlock certificate and launched it back in the air. It flew 64% of the mission and then it came back to starting point for a new battery.  Once I put the new battery in, I went through the steps for the certificate again and launched it back up. It went to the 64% mission spot but just hovered and hovered & wouldn't complete my mission. I tried with 3 other batteries and same thing. I was out of ideas, and of course the job site is 2 1/2 hours driving each way.

Has anyone had this happen? If so, what did you do?

Haven't had exactly that happen but I'm not at all surprised. Lots of DJI flight restriction horror stories here. DJI needs to get out of the business of telling us where we can and can't fly. As professional pilots it is our responsibility to only fly where appropriate and only after obtaining any required clearances.  As somebody who has been financially harmed by DJI's attempts to regulate how we use the tools we purchased from them, this is a definite sore spot.