Swift4: Forced cast from 'Data?' to 'Data' only unwraps optionals; did you meant to use '!'?

at the last update to Swift 4, im always getting the same error at the same spot and i don't know how to clear it...

if tried to use ! instead of ? but the error keep going in the opposite direction.

the Error is with both Date? and Data?

thats the code:

let done = UITableViewRowAction(style: .normal, title: doneTitle) { action, index in
        tableView.beginUpdates() // Beginne mit dem Update


        // error in the following line
        self.appDelegate.loanResource.editLoan(withObjID: (loan?.objectID)!, andName: (loan?.name)!, andAmount: (loan?.amount)!, andNote: (loan?.note)!, andCreated: loan?.created as! Date, andDue: (loan?.due) as! Date, andDone: nowDone, andImage: loan?.image as! Data, andContactInfoMail: (loan?.contactInfoMail)!, andContactInfoNumber: (loan?.contactInfoNumber)!, andChargeMode: (loan?.chargeMode)!, andChargeAmount: (loan?.chargeAmount)!, andReminder: (loan?.reminder)!, andReminderID: (loan?.reminderID)!)


        UNUserNotificationCenter.current().removePendingNotificationRequests(withIdentifiers: [(loan?.reminderID)!]) // Reminder entfernen, weil der Betrag zurück gezahlt wurde
        tableView.reloadData()
        self.loanList?.remove(at: indexPath.row) // Datensatz aus der Variable entfernen
        tableView.deleteRows(at: [indexPath], with: .fade) // Datensatz ausblenden
        tableView.endUpdates() // Update beenden
        vc?.setTotalAmount() // Gesamtwert aktualisieren
    }

all other errors are gone, but this one keeps my head smoking.

Assuming all types inside loan match the expected types the following should work:

if let loan = loan {
    self.appDelegate.loanResource.editLoan(withObjID: loan.objectID, andName: loan.name, andAmount: loan.amount, andNote: loan.note, andCreated: loan.created, andDue: loan.due, andDone: nowDone, andImage: loan.image, andContactInfoMail: loan.contactInfoMail, andContactInfoNumber: loan.contactInfoNumber, andChargeMode: loan.chargeMode, andChargeAmount: loan.chargeAmount, andReminder: loan.reminder, andReminderID: loan.reminderID)
    // more to to with the unwrapped loan
} else {
    // loan was nil
}