There are several factors that may cause this issue, unstable power source or faulty cable most likely,
1. Faulty/unstable connection /cable, port, or power source issue,
Please unplug and reconnect all cables gently again,
Please try below 3 alternative cables/ports/ power to troubleshoot.
2. Firmware or setting issue,
Please try the firmware update and reset the cam at the last chance,
https://support.viofo.com/support/solutions/folders/19000140970
two ways to reset the cam, choose the Default setting on the menu or press the Reset hole on the side of the cam,
3. Faulty cam body itself,
You shall update the firmware to seek a chance,
https://support.viofo.com/support/solutions/folders/19000140970