Today I uploaded my first build of first app successfully to App Store for beta testing. After making a few changes, when I tried to submit the new archive again Xcode crash
You might need to accept some new user agreements, try going to Apple Developer Member Center and see if they're any new agreements you need to accept.
If that doesn't work try this: open Xcode and go to [ Preferences ] -> [ Accounts ], select your Apple ID and click on [ View Details... ]. Once you do that click on the refresh icon at the bottom left. If you're missing anything it will let you know.
If both of those don't work go back to the archive window in XCode and click on export on the right-hand side underneath the submit button. Save it where ever you want but remember the location. Once exported go back to XCode and go to [ Open Developer Tools ] -> [ Application Loader ]. You can submit your new version of your app through that.
If none of those work then I have no idea, maybe someone else knows.