I would contact their support. It's a horrible system, because there are no real people that you can talk to. You have to sit there & type out questions, then wait for the translator in South Korea to give you an answer. Last time I logged on & typed away - it took over 40 minutes, & all I got was ½ of my solution, at which point they just disconnected us. Not looking forward to having to get back on & typing for another protracted session. We dropped our files down from 3 minutes to 1, just because it's easier to find stuff by looking at the little still shots prior to loading & waiting for the horribly slow buffering that the wifi system provides. If we ever get this thing dialed-in, we will make sure to never ever change settings again.
Pull the microSD from the camera, then use the supplied USB adapter to plug the card into a suitable PC. When the card mounts as a drive, open up the \Blackvue\Config\Config.ini file in a text editor. Review the settings within (or paste the "[Tab1]" section here for review). You're looking for the "NormalRecordTime" setting, and it should be set to 3. Don't try to set non-standard values here, they likely won't work.
If you change anything, reinsert the microSD back into the camera and power it up. The camera will read the Config.ini on startup. See if that fixes your normal recording lengths.