Tue Dec 12 2017 20:08:00 UTC
Keep calm and do a clean rebuild.
Hide Search Description
ID Product Comp Assignee Status Resolution Summary Changed
59855 Xamarin iOS code oleg.demchenko CONF --- "Add Team" UI no-ops and spawns dialog ordering user to use Fastlane 2017-10-26
60335 Xamarin iOS code oleg.demchenko CONF --- [Entitlement Editor] Add 'Download HomeKit Simulator...' button in VSMac 2017-10-23
60861 Xamarin iOS code oleg.demchenko CONF --- Automatic signing failed: Your session had expired. Please log in. 2017-11-29
60905 Xamarin iOS code oleg.demchenko IN_P --- FAstlane Automatic signing failed: Cannot cast Newtonsoft.Json.Linq.JArray to Newtonsoft.Json.Linq.JToken. Thu 02:22
4 bugs found.

as

File a new bug in the "iOS code signing" component of the "Xamarin Studio" product