Just wanted to share the solution from a problem not yet adressed on stack overflow apparently.
From XCode, when trying to distribute an iOS app on the app store (via archive => distribute), I face this error :
App record creation failed due to invalid input. Request failed with error code "STATE_ERROR.APP_CREATE.PLATFORM_NOT_ALLOWED_DUE_TO_CONTRACT_STATE", and reason "One or more platforms cannot be created for this app due to your provider's contract state. Creation of apps for the platform(s) iOS is not available due to your provider's contract state."
