How to reload freeradius service after new NAS added without restart

Hi All, I am trying to reload freeradius config after adding NAS but it's not working, and it is only work with restart.. On "service freeradius reload" it's showing this error.. " * Checking FreeRADIUS daemon configuration... [ OK ] * FreeRADIUS daemon is not running " i also tried the with sig HUP but still it's not working. Please help if anyone have idea about this. Thanks Imdad