On various occasions, when I come to launch the Mavic Air 2, doing the movement on the joysticks on the controller to get the drone to start up and then using the joystick to elevate do not work. I.e. no response.  Pressing the icon the phone's screen allows the drone to take off but it hovers at about 1.2m and the joy sticks do not work to get it to go up or down nor to move forward, backwards or to crab.

One day it works, the next day it does not.

Any ideas?

It will help with the troubleshooting if you can provide the Smart device type, (Android/iOS) the Fly App version, and which MA2 firmware you have in the drone when it responds this way.  Is the area you launch in wide open? What mode are you flying in with the remote? (cin/normal/sport) How do you have your obstacle avoidance configured in the FLY App?

Hello there JDG500. I am sorry for the trouble this has caused and thank you for reaching out. May we please know what is the model of the mobile device that you are using please and kindly please try to uninstall and reinstall the DJI Fly application ( https://www.dji.com/downloads/djiapp/dji-fly ) for us to be able to isolate the said issue? In addition, kindly please sync all of your flight records before uninstalling the DJI Fly application on your mobile device for you not to loose your previous flight information. Thank you.

Sounds like a defective remote control. Have you done a calibration of the remote?