Challenge Formatting the Date

In the Crime Data Class how would I cast the Data to a DateFormat Object and then use that object in the Fragment? I am using

    fun bind(crime: Crime) {
        this.crime = crime
        titleTextView.text = this.crime.title
//            Chapter 10 Challenge: Formatting the Date
            dateTextView.text = this.crime.date.getLongDateFormat()
            solvedImageView.visibility = if (crime.isSolved) {
                View.VISIBLE
            } else {
                View.GONE
            }
        }

And Note having any luck