Testflight tab not loading (HTTP 500)

We are having trouble with Testflight. The Itunes Connect tab keeps loading forever.

Behind the scenes, the XHR queries related to our App are returning 500:

e.g.

https://appstoreconnect.apple.com/iris/v1/apps/<app_id> is returning

     "errors": [{           "status": "500",           "code": "UNEXPECTED_ERROR",           "title": "An unexpected error occurred.",           "detail": "An unexpected error occurred on the server side. If this issue continues, contact us at https://developer.apple.com/contact/."      }] }

Anyone else having the same problem?