Because the purchase was cancelled, the 60-day rollover deadline becomes extended to 120 days. Completing the rollover on the 67th day following the distribution is within the deadline. (This assumes that you indeed met the qualifications to be a first-time homebuyer were it not for the fact that the purchase fell through.)
Provided you did not roll over any other IRA distributions in the 12 months proceeding this distribution, this distribution was properly rolled over. Simply report the rollover as you would any other by entering the Form 1099-R and indicating in the follow-up that you rolled the distribution over.
