This is a forum, not a realtime chat. People respond to posts as and when they get on.
The same applies to join requests, for that matter. If the people who manually process them have not been online, or had time, it will take longer. Those people are the only ones who can give you an actual answer.
24 hours is the usual response time, but it's not a solid deadline or anything.
"May the Grace of Ara go with you, and His Vengeance be wrought upon your enemies."