1080p production time: When your video is created on Create, it will initially save in 720p resolution. Afterward, the backend works to create a 1080p version. This process may take a few minutes before you can access to 1080p version.
Footage used in your videos: Make sure you use high-resolution footage (photos and video clips). Your source footage should be at least 1920x1080 resolution to achieve the full HD version of the video.