Same issue
[!] Error uploading ipa file:
[Application Loader Error Output]: ERROR: REQUEST CREATE CONTAINER (ASSET_UPLOAD): received status code 500; internal server error. (500)
[Application Loader Error Output]: Error uploading '/Users/ci/buildAgent-1/temp/buildTmp/5dd768d6-6f07-4cf9-adf8-85a300aca08a.ipa'.
[Application Loader Error Output]: An unexpected error occurred An unexpected error occurred on the server side. If this problem persists, please contact us.