heya, welcome! a couple of things to point out -- first off, make sure you check out what the valid file types are for any given OHB. the page tells you what format the battle is, and you can click "read lyceum article" to find out what to do. (for example, you submitted .webm to jummbox which requires .txt, and .mp3 to adlib which requires a module file of various sorts or .vgm)

there are a handful of formats where .mp3 is okay, but not the vast majority of them : )

second of all, OHBs are started from scratch when the timer starts, and there will be a prompt ("bit pack") for you to read/download that you have to follow to ensure that you are doing all your work within the 1 hour. i noticed you submitted your entry immediately when the battle started, so keep that in mind.

feel free to peruse the Lyceum for more info on how the site works, it's like our wiki!