Cannot view data on the graphic (return nan on the graphic)

[nwts90]

Dear all,

Please help me to solve my cacti problem.
Some day I cannot view the traffic data on the graphic (return nan on the graphic).
However, I can view traffic data on real time traffic.

I did snmpwalk on this OID and return below result.
SNMPv2-SMI::enterprises.2603.5.4.2.1.8.3.52.89.48 = Counter64: 0