If anyone else is having this problem you need to change the Domain in Configure URLs section.
When I had “Bucket name in path” selected, the URL was completely wrong for the files. It would show:
https://s3?us?east?1.amazonaws.com/
when it needs to be
https://s3.amazonaws.com/
Just copy the path where your files are being uploaded and paste it into the “CloudFront or custom domain” selection.
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