My grand stream GXP162 phone disconnests the call after 6seconds of placing the calls

Hii Guys I have Grandstream GXP1400 which is working fine but recently i bought Grand stream GXP162 which automatically disconnects the phone ie., in within 6 seconds the call gets closed , but in same environment the older verson of grand stream phones(GXP1400) are working good.
And my FreePBX version is , it would be of great help if u guys help me with this problem .


Can you please open a ticket with the Grandstream help-desk, we would be happy to assist you. Here is a link to the help-desk;

Thank you,