Optional faxErrorCode
faxErrorCode: "Undefined" | "NoFaxSendPermission" | "NoInternationalPermission" | "NoFaxMachine" | "OutgoingCallError" | "RenderingFailed" | "TooManyPages" | "ReturnToDBQueue" | "NoCallTime" | "WrongNumber" | "ProhibitedNumber" | "InternalError" | "FaxSendingProhibited" | "ThePhoneIsBlacklisted" | "UserNotFound" | "ConvertError" | "DBGeneralError" | "SkypeBillingFailed" | "AccountSuspended" | "ProhibitedDestination" | "InternationalDisabled"