Let's say it's for something petty-ish. Like they grabbed the last mango at the supermarket that you had your eye on and were walking over to get it. Idk you're the witch so you can choose your level of vindictiveness. Explain what they did if it's fitting in with the curse.
You could curse them so they can never say whatever day of the week it is at that time, they can only say it relative to a day that's either three days before or three days hence.