FOP operator panel error

I have freepbx 2.11 and asterisk version 11.4 and I am getting the following FOP error. Any ideas how to fix this issue?

Could not reload the FOP operator panel server using killall -HUP Configuration changes may not be reflected in the panel display. If the FOP module was just installed you may have to retart Asterisk with the “amportal restart” command for the FOP server to run.
Added 10 weeks, 1 days, 23 hours, 15 minutes ago

Please let me know how to fix it has been occurring since I installed. Thank you in advance.