[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 am writing to inform you that I was unable to attend [work/school/event] on [specific date] due to [brief reason for absence, such as illness or a personal matter]. I apologize for any inconvenience this may have caused.

Please let me know how I can catch up on any missed work or tasks.

Thank you for your understanding.

Sincerely,
[Your Name]