1. The video of face authentication is unclear: when performing face authentication, make sure that there is enough ambient light and the face is clearly visible. Try to choose an environment with moderate brightness to ensure that the camera is aimed at your face.

2. Unstable ambient light: Unstable light will lead to face recognition failure. Face authentication should try to choose a stable light environment to avoid strong backlight or shadow.

3. Mismatch between the head and the video frame: When performing face authentication, ensure that the position and angle of the head and the video frame match. Put your mobile phone or device in a proper position to ensure that your face is completely displayed in the video frame.

4. Network abnormality: Unstable or slow network connection will lead to face verification failure. Make sure your device is connected to a reliable network, and try to perform face authentication in an environment with good network signal.

5. Face recognition parameters do not meet the requirements: Bank of Communications App has some requirements, requiring specific face angles, expressions or obstructions. Please ensure that face authentication is performed according to the requirements of the application.

6. Poor image quality: The poor quality of photos or videos taken will lead to the failure of face recognition. When carrying out face authentication, try to choose clear and high-quality photos or videos to improve the chances of successful authentication.