Okay, solved! problem belongs to plivo, FS is right now, On Sat, Aug 23, 2014 at 12:00 AM, S.Mohammad Emami Razavi < emamirazavi@gmail.com> wrote:

With last version of plivo and FS Version 1.5.13b when call is hanged up, wonderfully hangup url in plivo is not called although event is detected by plivo!!! I think it's probably a problem about new versions of FS because plivo stays without change in several months ago, anybody any idea?!