Got this PM from shivam12, who joined RCI just a few minutes ago.

"Need help.
One more behavior I found that when I try to calibrate all ESC by pressing 1 and 4 button in kk 2.1 flight controller. Suddenly all 4 motor started spinning at same time but once the throttle pass thru screen goes off, motor spinning stopped and it never ran even after full throttle."

Can some multirotor guys help him?

@shivam12,
Follow this thread.
Regards.

Even I had the same issue at first but then found the solution to it.If you are using blheli firmware escs then you should calibrate each escs individual at first . After that you can calibrate all the four escs through the board without all the motors spinning while calibrating . Remember that you can only do the all 4 escs calibration once without motor spinning. If you try to do it again the motors will just spin when you calibrate the escs.

Need more Info. Which ESCs and what firmware are those running with