I had this same issue and it resolved by making sure it logged in with the correct account.
When the modal dialog asks to select a "Development Team to use for provisioning"
Choose "View Accounts..." make sure the correct account shows in the "Apple IDs" list.
If the Apple ID is not there, use the plus sign to add a new Apple ID account.
Close the Accounts screen.
On the "Development Team to use for provisioning" use the drop down to select the account you just added, select Choose and then Validate and it will work.