I am in an open field. The closest trees are 30m away. As soon as my Air 2S is in the air the controller starts beeping. The only way not having this beeping is setting the RC in sports mode. The suggestion disable volume of Iphone is not the proper solution. What does this beeping tell me?

Thank you for the posts I received. The beeping was quite alarming to me. It gave me the impression there was something seriously wrong with my drone and therefore I landed the drone quickly.
I now understand the beeping is a warning signal from one of the sensors of the drone. Tomorrow I will try again, ignoring the beeping???
Today I calibrated all the sensors and YES that resolved my problem. Little hint for the next release of the user manual, mention the beeping sound being part of the vision system.

Thanks to everybody who answered to my post

From Manual:

Remember its not just front or rear, but front/upwards (or as I like to think of it as front diagonal). Any of those area will trigger the beep warning.

Hello there Dutch799. I am sorry for the trouble this has caused and thank you for reaching out. Before this issue happened was there a hard landing or a crash that happened to your DJI Air 2S and can you please try checking the sensors of the said DJI drone as well to see if there are damages or debris that are obstructing the said sensors. In addition before doing another flight kindly please try to calibrate the said DJI drone as well for us to be able to isolate the said issue. Thank you.