已有约会 meaning in Chinese

have previous engagement

I ' m sorry i can ' t come on saturday , i already have something on
对不起，星期六我不能来了，我已有约会在先了。
Because of a previous engagement / full schedule / business trip , i can ' t make it at the time
由于我届时已有约会全部时间已经排满另有事务性访问，故不能出席。
Because of a previous engagement / full schedule / business trip , i have no choice but to cancel the appointment
由于我届时已有约会/全部时间已排满/出差，故不得不取消约会。
I / we regret that i / we can ' t make it because of a previous engagement / full schedule / business trip at that time
由于我们届时已有约会全部活动已排满需要出差，故不能出席此次晚餐午餐，实为抱歉。