Coming late for an appointment

1. I just plum forgot.
2. It slipped my mind.
3. Forgive me, I just didn’t remember.
4. I didn’t do it on purpose.
5. I hope you understand.
6. Please don’t take it personally.
7. I knew I forgot something.
8. I’ve been burning the candle at both ends.
9. I’ve been crazy busy lately.
10. I have a lot on my plate.
11. The time just slipped through my fingers.
12. I just have no sense of time.

Coming late for an appointment