Mission Planner SITL

Hello everyone,
I’m new and trying to use Mission Planner SITL, After a while after loading the flight plan and pressing the ARM button, it becomes Disarm. How can i fix it

It’s probably just timing out. Give it command or disable DISARM_DELAY (set to 0)

thank you so much it’s fixed, but now it responses PreArm: 3D accel calibration needed