Yes, you can use a new microSD card if you do not want to record over existing videos by removing the side cover on the camera and replacing the exiting microSD card with a new one as long as it does not exceed 128GB. Once this is completed you will need to format the microSD card by going to the SD Card Settings in the Settings menu and pressing Format SD Card then Confirm.
WARNING: Reformatting microSD card will delete all content stored on card.