The NFA Console shows Netflow data coming in, but the interface information from the device, that comes in via SNMP, seems to be incorrect.
This can also prevent an individual interface from being Licensed, and also cause Auto Enable Interfaces to be disabled on its own.
The \Reporter\logs\Pump*.log will have a message like below:
13:30:17 4 - DataConverter - Failed to create agent for <ip address> ::436744192:
NQS_BUS_20000: Received data for virtual interface <ip address>::436744192 which does not exist.
NetQoS.ReporterAnalyzer.Business.Pump.i18nDataDiscardedException: Received data for virtual interface <ip address>::436744192 which does not exist.
The ID in the error message, is over the value NFA expects and gets treated as a Custom Virtual Interface which does not exist.
Disable Netflow from the device in the error message.
Upgrade to NFA 9.3.3 where the IfType Exclusion rules should reduce the change of this happening.
Defect DE37889 has been submitted on this for reference.