Dear [Recipient's Name],

I hope this message finds you well. I am writing to sincerely apologize for not being able to keep our scheduled meeting last week. I understand that my absence may have caused you some inconvenience, and I truly regret the disappointment it may have brought.

To be honest, there were unexpected circumstances that arose at the last minute, which made it impossible for me to attend as planned. However, I realize that no excuse can justify my failure to inform you in advance. I should have communicated with you earlier and given you proper notice, so that you could make alternative arrangements if needed.

Please know that I value our time together and the importance of our relationship. I take full responsibility for my mistake and would like to make it up to you. If possible, I would greatly appreciate the chance to reschedule our meeting at your earliest convenience. I am more than willing to adjust my schedule to accommodate yours.

Once again, I offer my sincerest apologies for the inconvenience and frustration this may have caused. I hope you can forgive me and give me another opportunity to show my commitment to our collaboration.

Thank you for your understanding and patience.

Warm regards,

[Your Name]