I was having trouble uploading to the platform, I kept getting error messages for about two days also until I refreshed the page and it all of a sudden just worked. It was massively frustrating before this. Something to do with the snap image of all things and IPFS problems so it said.
I did see some people saying they were having problems until they used chrome browser also. I don't like chrome because google owns the monopoly on spyware, but I use a similar browser called Brave which I think is a better.
I hope you manage to sort out your upload issues.