What am I missing?

Ive been trying to install and configure SSU with S3 and I am getting this error. File doesnt upload and “Failed upload Error”

DEV tools:

Failed to load resource: the server responded with a status of 400 ()
index.js:9 Uncaught (in promise) Error: Request failed with status code 400
    at e.exports (index.js:9:1)
    at e.exports (index.js:10:1)
    at XMLHttpRequest.p.<computed> (index.js:9:1)
upload.php:1 Access to XMLHttpRequest at 

from origin 'https://cli-main-dev.uth.tmc.edu' has been blocked by CORS policy: Response to preflight request doesn't pass access control check: No 'Access-Control-Allow-Origin' header is present on the requested resource.Failed to load resource: net::ERR_FAILED

When I look at the XML file in the DEV Tool:

<Error>
SignatureDoesNotMatch
<Message>The request signature we calculated does not match the signature you provided. Check your key and signing method.</Message>

Please help