I too got the message "There was an error processing your request. Please try again later". But on inspecting the issue in the browser DevTools got the error to be: "ENTITY_UNPROCESSABLEMISSING_BETA_APP_DESCRIPTION" Go to AppStore Connect app on the mobile and try again. On reaching the step to add builds, it gave me the warning that the Beta App Description is not set and a button to go to the screen and fill it up. The comment from greensopinion is what saved me. Jun 23 I've encountered the same issue. For a workaround, I was able to submit the build to TestFlight using the AppStore Connect app on my iPhone instead of using the website.