[Your Name]
[Your Address]
[City, State, Zip Code]
[Email Address]
[Phone Number]
[Date]

[Recipient Name]
[Recipient Title]
[Company Name/School Name]
[Company/School Address]
[City, State, Zip Code]

Dear [Recipient Name],

I hope this letter finds you well. I am writing to inform you that I was unable to attend [work/school/event] on [specific date(s)] due to [briefly state the reason, such as a personal matter, illness, or other reason]. I apologize for any inconvenience my absence may have caused and appreciate your understanding.

Please let me know if there is anything I can do to catch up on missed work or to assist in any way. Thank you for your consideration and support.

Sincerely,
[Your Name]