I am not sure what is happening. It seems to just sit and “wait” after running 3 passes on a 3D Grid mission.
It seems to sometimes work after shutting everything down and starting again, but I would like to know if there is a solution to this problem.
Are you using Pix4Dcapture on Android or iOS? Also could you please provide more information about the drone and the camera used? I would suggest to check the recommendations of this article for an optimal experience:
https://support.pix4d.com/hc/en-us/articles/115004119343