The map itself is missing from the osz on the site, so you most likely have unicode characters in a place where the game doesn't want them to be (for example cyrillic characters in the name of a difficulty or file). Remove them from anywhere except the unromanised artist and title fields and tags and try again.
Could you upload the map somewhere else? Go to File --> Export Package, then upload the .osz file in any file hosting site available (for example, Discord), and then link it here so that we can properly analyze what exactly is going on.