Hi [HR/Interviewer Name],
I hope this email finds you well. I am writing to apologize for any inconvenience that this may cause, but I would like to reschedule my interview that is currently scheduled for tomorrow evening at 4 PM.
Unfortunately, something unexpected has come up and I will not be available at that time. I would be extremely grateful if we could reschedule the interview for the following day at the same time. I assure you that I am still very interested in the position and would be eager to discuss my qualifications with you at a more convenient time.
Thank you for your understanding, and please let me know if there is any additional information that you require.
Best regards,
YOUR NAME
