I am not familiar with this older Viofo model, it could also be it is able to enter parking guard in the old fashioned way, which mean after X time of no movement / G sensor activity, the camera change.
It could also be that you can turn on parking guard, but ti never chage to that due to missing hard wire kit, you will have to experiment a little to see if it change alright.
Put camera on something solid so G sensor dont get triggered by accident, aim it at something so motion detect dont trigger, if possible try to use the low bitrate mode, this is easy to see among regular files as it make much smaller files,,,,, if you ask to see properties on the movie clips you can also see the bitrate on a clip, low bitrate are only 6 mbit or so, where regular recorded files are much higher bitrate.