[Freeswitch-users] calling again if the receiver hangsup

Hi, I am using freeswitch server for android softphone development. When i am calling from my softphone to a mobile number, and if the receiver of the call hangs up without answering. then i am getting voice mail message from the receiver end. and The mobile number at the receiver end is receiving the call again. please guide me which channel variable i must set in my sip providers dialplan, so that the call is established only once. This behavior is not happening when i call between freeswitch extention to freeswitch extention. Regards.