Apology Letter For Oversleeping
Dear {Recipient},
I'm so sorry I overslept and missed our {meeting/brunch date/etc.} {this morning/yesterday/etc.}. I had set {number of} alarms on my phone to make sure I would wake up on time, but unfortunately that didn't work. I guess I was just too tired from {last night/the night before}... I was up all night {working/studying/etc.}.
Do you want to reschedule for {next week/tomorrow/etc.}? I promise I won't let you down again.
Sincerely,
{Your Name}