my coworker broke her appointment

It is dragon boat festival today. My coworker asked me to go to shopping next day last night, we want to go to supermaket to buy 粽子. It is tradition to eat Zongzi in the festival. My parents did it themselves when I was childhood. But less and less people know the skill how to make Zongzi nowaday. I called my coworker after got up, but she told me she couldn't go with me because she got a phone call from her sister and she had to go to her sister's home. Then I couldn't go out with her today, and I slept all day, but I still couldn't regain energy from night shift.