If the aircraft information (e.g. battery info, RC signal, etc.) is shown in the DJI GO app while the camera's information is not, check if the gimbal camera is correctly assembled and can conduct the self-check normally.
If the camera works normally, check whether there is cosmetic damage to the USB port of the remote controller and the USB cable is connected correctly. If not, try with another mobile device.
If the USB cable and the mobile device work normally, try with another remote controller. If there is no another remote controller available, connect the remote controller with an HDMI display. If the HDMI monitor works normally, the USB port on the remote controller is malfunctioning.
If the issue persists, the aircraft may be malfunctioning. Please send the aircraft to DJI for diagnosis.