Check if your cruising speed is not zero.
Sounds like high wind velocity.
At WP1 press the pause button, wait a few seconds then continue the mission.
I never heard of this message, most likely “Actions are disabled with curved turns”
The curve size at WP1 is always zero, a curve can only exist between 2 lines, i.e. 3 points.
It would be helpfull if you shared your mission in the Mission Hub: