You should have all your AM account info on the top right of the page when you log in. My AM has always contacted me immediately after I email him.
I suggest to you to check your payment history and see if you still reach the threshold for that month , because they let the advertisers to return as many as they want from the publishers conversions. another thing is to provide them with the w8 form(if this is your first payment) try to contact Shauna by AIM ( MotiveShauna )she is a very supportive , nice accounting manager , i don`t know if this AIM will work with you because i stopped to promote their campaigns 2 months a go.
Nakata, Send me a PM and let me know what your name is and I will get this sorted out for you. Our terms are $100 threshold for payment and we are on a Net30 system.