There could be a few reasons why you see a black screen when trying to play your uploaded video:

• The video Upload consists of multiple parts that do not come from the same camera. This can cause issues in the background. All parts should have the same resolution, framerate, and audio format. It is best to use footage from the same camera. If you still want to use different sources, you can try importing the video files into another program on your laptop, exporting them as one complete video, and then uploading it to TeamTV.
• If you Upload one or more video files, it is possible that one of these videos is corrupt. This could be due to recording errors or issues with the camera. To check for corruption, play each part that you want to Upload on your computer. If any part does not play correctly, that could be the cause of the problem. TeamTV does not support corrupt video files.