nagiosxi strange issue

Hi Experts

we have in our environment NAgios-XI  the commercial version of Nagios

and i am monitoring file systems under red-hat box  and everything was ok no issues

yesterday i extend the filesystem from 1.3 TB to 2.9 TB and after one day i start to get critical massage from Nagios-XI


[root@nagios ~]# /usr/local/nagios/libexec/check_nrpe -H 192.168.42.11 -t 30 -c check_disk -a '-w 50% -c 80% -p /oracle/RAN/oraarch'
DISK CRITICAL - free space: /oracle/RAN/oraarch 2291546 MB (77.93% inode=100%);| /oracle/RAN/oraarch=648895MB;1471509;588603;0;2943018


but this is not true the file system status like this


/dev/mapper/oraarch-oraarch                         2.9T  632G  2.2T  22% /oracle/RAN/oraarch



so only 22% used from this file system

i am monitoring another file systems on the same box and the everything ok just this file system so it cannot be agent issue on the red hat box


any idea here



thanks
Sword