PreArm: Need position estimate in guided mode

Hi. We have a problem about guided mode.
When we change to guided mode from stabilize mode, the message ‘PreArm: Need Position estimate’ occurs. In the screen of mission planner, we can see ‘GPS: 3D fix’, and we give home position and the goal position.
Why does this problem occur?
Please teach me.

Hi @NK_AA ! The problem seems to be similar to your other thread. It’s better continue there.