Panel does not display

I have a 2.5.1.2 FreePBX installation on Debian.
Everything has been working OK for few weeks but now when I want to display the Operator Panel i click on the “Panel” tab which links to http://192.168.1.200/admin/panel.php, the browser then displays “Waiting from 192.168.1.57” instead of 192.168.1.200 which is the address of the PBX and time-out.
Does anyone know why and how to change this wrong address?

change your amportal.conf on line AMPWEBADDRESS= to AMPWEBADDRESS=192.168.1.200

Totally right !
Thanks