Dialog bahasa inggris you have promissed your sister to accompany her go to tge boutique, but suddenly you cancel it

y=you, s=sister

s=hey, do you remember today's promise? that you could accompany me to the boutique
y=sorry about that, but can we go to the boutique another day?
s=why? you promised me today that you can
y=i have an appointment with one of my friends to study together
s=if it's study then no problem, study hard my brother/sister!
y=yeah, thanks sis.