Closing Accounting Sessions at the end of Month

[Ali Arslan]

Hi all,I am using freeradius 3.0.12 with mysql.I want to close all open accounting sessions at the end of month to be able calculate monthly usages.
Should i use radzap, or another better option?
When i tried radzap as:
radzap -N nas-ip radiusServer-ip secret
i get:
Sent Accounting-Request Id 4 from 0.0.0.0:39563 to radiusServer-ip:1813 length 38 #(3 trials)(0) No reply from server for ID 4 socket 3
What am i doing wrong?
Thanks.