To: [Insert name]
From: [Insert name]
Subject line: Rescheduling interview
Hi [Candidate name],
We need to reschedule our interview for the position we had arranged for [insert date and time] because our hiring manager will not be available on that day.
Are you available on [insert new date and time]? If this does not work for you, let me know a better date and time.
I apologize for any inconvenience.
[Insert email signature]