Mine seemed to be the same a while ago but when I followed the instructions given on here by Millie from Nextbase support it appeared that the battery was OK.
This is the procedure I followed and once done, the battery lasted just over a quarter of an hour:-
I'd recommend performing a battery test:
1. Unplug the Rear Dash Cam (if applicable) and remove the Dash Cam from it's windscreen mount.
2. Take the Dash Cam indoors and remove the SD card.
3. Using the USB cable provided in the box, plug it into a mains power supply (2 Amp recommended), make sure to plug the cable into the body of the camera, not through the car mount.
4. Go into the Dash Cam menu and make sure that Parking Mode is turned off (if applicable), if Parking Mode is enabled, this will affect the test.
5. Leave the camera on charge for 4 hours (or more) with the camera turned on. When fully charged, the blue charging LED should turn off.
6. Unplug the power cable, the camera should shut down.
7. Turn the Dash Cam on (using only battery power) and time how long it takes for the battery to run out and the camera to shut down.
Please note:
After performing this test, your Dash Cam will need to charged again, before reinstalling in your car.
Please let me know how long the battery lasts during the above test.
I will mention that the blue LED charging light went off after a few mins. but I kept it plugged into the power supply for about two hours just to make sure.