ANI-DTMF Problem

Hi there guys,
I Have a problem with ani-callback. The Problem is :

I dial the Access number,

The access number calls me back and asks me to enter my destination number, but when i press any number it does not detect them ???

And, the strangest thing is that
Upon gettins the ani server callback if i hear the IVR asking to enter my destination number and i press the numbers it does not detect
but when i don’t hear the IVR asking for the number it detects then when i press the numbers ??
Strange but i guess u guys gotta have a solution for this ![/code]

Thanks !