Conversations

I've runned in to some trouble with Conversation editing..
I've been following Tack's Conversation tutorial, and everything went great, i made like 2 working conversations, added some sound, everything was perfect... But there was one guy who i couldn't talk to, even though everything was all set and done.. When i click, I kind of bounce a little, like a bop.. i can speak to him sometimes, and sometimes i can't... I don't know what the problem is. anyone experienced the same issue as me? And how do i fix this?
I've been following Tack's Conversation tutorial, and everything went great, i made like 2 working conversations, added some sound, everything was perfect... But there was one guy who i couldn't talk to, even though everything was all set and done.. When i click, I kind of bounce a little, like a bop.. i can speak to him sometimes, and sometimes i can't... I don't know what the problem is. anyone experienced the same issue as me? And how do i fix this?