I purchased some stock footage - someone using a computer but the screen is green screen. I have tracked and replaced the screen with my own content. When I go to export, the content disappears and only the green screen appears.
I've included an image below. In the top left corner of the first picture it shows the green screen but the composition doesn't, and then the exported video.
I've done this with other videos and it exports fine, so not sure where I'm going wrong. Any help would be appreciated.
I have no idea what's going on because you did not give us details about your workflow or render settings. the most obvious problem would be that you rendered the Footage Stabilized nested comp instead of the Screen Tracked comp.