Analog Card Disconnection Problem

Hi i have installed an Analog Card, but i have disconnection problem, at the moment that the calling party hangup , my internal extension continue ringing,

i uncomented the line


but doesnt work any suggestion?

How does your network operator signal disconnect?

Solved test with a different line from connected directly to to the FXO port and everything work fine, the problem was that i was using before an external GSM device (TELULAR) with an FXS port connected to an FXO port on my Asterisk Card, and when the caller party discnonnected the call the signal was passed to the GSM device but no passed to Asterisk