The battery indicator shows fully charged, but the LCD display is flashing no battery. Please check it as following steps.
1) Replug the display cable and reboot.
2) Check if the main cable on the controller is loose.
3) Download the Heybike APP and bind your ebike. Then click the small gear settings button in the upper right corner, and try "Restore Factory Settings" to fix the problem.
4) If it still does not work, please contact Heybike Support and kindly provide photos or a short video of this issue.