I was supposed to go to Japan, but I had to cancel it.
I was supposed to travel, but I couldn’t.
I was supposed to watch baseball, but I didn’t.
I was supposed to work, but I couldn’t.
I was supposed to run a marathon, but I changed my mind.
I was supposed to go to your party, but something came up.
I was supposed to see you today, but I have to cancel.
I was supposed to go to his party, but I was really sick.
I was supposed to call you, but I fell asleep.
I was supposed to relax, but I couldn’t.