asterisk users - May 2005 - TDM400P with 2 FXS module fail to Hangup

Hi all:

I am located in Australia Sydney. We had two PSTN line connected to
TDM400P card. The problem I am having is Asterisk cannot Hangup incoming
PSTN call. Even Hangup function is called. Tried to search few days and
asked different people but without luck, any help will be appreciated.

Regards,
Paul Yiu