Failed to upload to AmazonS3 (cURL resource: Resource id #1855; cURL error: SSL: no alternative certificate subject name matches target host name sitename.s3.amazonaws.com' (cURL error code 51). See http://curl.haxx.se/libcurl/c/libcurl-errors.html for an explanation of error codes.).
just needed to change the bucket name on Amazon s3 to simply solve the issue