Airspeed sensor issue

Am using pixhawk cube ( Black) .am using digital airspeed sensor(Ms 4525d0) .it is connect to the i2c port .
Arspd_ autocal =0
Arspd _bus=1
Arspd _ offset = 64.39894
Arspd _ pin =65
Arspd _ psi range =1
ratio = 1.9936
Arsped tube order =2
Arspd type 1
Arspd use 1

When am calibration it not showing 0 value pitot tube is closed also it showing 1.2m/s like that showing .when blow the air it showing some value…
Preflight _ calibration > do action am calibrating proceed …
How to set 0 value

From -

If you see mostly 0, 1, 2, with an occasional bounce to 3 or 4, consider it normal

So, what behavior you’re describing is normal.

Thanks for the reply