I can't be there today/at noon.
I can't make it this weekend.
I can't make the date/meeting/appointment.
Why didn't you come/show up?
Why did you stand me up?
Why did you blow off our date/ the meeting/the appointment?
You owe me.
You had better make it up to me.
A: Why didn't you show up yesterday?
B: Something came up and I couldn't get away. I'm really sorry.
A: Did your phone break too? Why didn't you call?
A: This is the second time this week you stood me up, what's going on?
B: Sorry, I'm really sorry, but I've got so much work these days.
A: Sorry, honey, but I'm not going to be able to make it. Something's come up.
B: What? It's our anniversary. I've been looking forward to this for a long time.
A: I know, I know. I promise I'll make it up to you. But something came up here at the office and I'm not going to be able to leave for a while.
B: Why does this always happen when we have plan? Are you sure you even wanted to go out tonight?
A: Yes, I swear. I was looking forward to it, too. I promise I'll make it up to you this weekend. But I really have to go now. This meeting can't wait.
B: Alright, but don't forget you owe me.