Video banner heading being cropped

I've edited a video in 16:9 aspect ratio, as recommended by Squarespace, but when I upload the video to my banner heading it crops off about 1/5 from the top of the video. The banner is set to its maximum height L and to fill screen. I've tried changing the aspect ratio (same problem occurs) and making the section bigger by adding rows (just zooms into the video). Any ideas please?

Thanks

Will