Audio missing

After finishing editing, browser was stuck on "we're still working on saving changes" and wouldn't let me download. I left the tab open for a long period of time, but this never finished. I closed the tab and reopened, and now the audio does not work. I've attempted to delete the added audio, close all browsers, and re-open the project. Then, added audio again. There is still no sound. When downloaded, there is also no sound.