When trying to upload audio assets on the Create page, the option to upload .ogg files is for some reason greyed out in the browser popup window. This is not specific to this audio either, I’m running into this issue universally with all .ogg files.
This is on MacOS Mojave 10.14.6 with Safari 13.0.1
The .ogg format appears to be unsupported on Roblox, or it’s just a bug.
Anywho, if it continues, just convert it to a .mp4 file, and I believe it’s higher quality anyway.
Also, uploading MP3s in the meantime is a decent solution, but it has caveats. The most notable is that .ogg files are perfectly loopable, and MP3s aren’t. If you need looping audio and oggs aren’t working, don’t upload an MP3 because you’ll waste your money.