When the scooter has kickstart enabled, this means you will need to kick the scooter forward to be able to get the motor going when you push down on the throttle. When it is turned off, the throttle alone will start the scooter.
Follow this step-by-step guide to change the kickstart settings in the App:
Go on the app, then click on the 3 dots on the left side of the Ride button, then click on the setting icon
Scroll down and disable the Kickstart option.