Upload Error isn't Descriptive

First, the Feedback link under support just forwards to https://itportal-tcp.corp.amazon.com/ is there another place to give feedback besides "asking a question"?

I attempted to upload a file to workdocs, and was getting constant errors:

I eventually decided to see what errors I was getting in my network traffic and saw a 400 response with this:

Fix the displayed error to show what the actual problem is and not "not successful, try again". Many people who use Workdocs will not know how to do this or know how to troubleshoot.