portion of video is black

Someone please help me!

I've been editing for a while and I went to select a large portion of my video to change the label color and now a huge portion of my video is black. There are green bars at the top but there's a huge gap and inbetween that gap is where the blacked out video is. I can still hear the audio but nothing plays on the screen. I've tried rendering it, and changing the video rendering and playback renderer to software only.