While checking nagios status in one of the node getting this error, seems this is not a bug in another node nagios service is running fine. Tried to remove the lock and check the nagios status but no use,
Here is the simple solution to resolve the issue,
/usr/local/nagios/bin/nagios -d /usr/local/nagios/etc/nagios.cfg
Run the above command and restart the nagios service that will resolve the nagios service lock issue.