The Harvester-wrapper.log file is showing us that the flow count on this harvester is 0 because all the flows are being dropped:
INFO | jvm 1 | 2021/07/15 15:13:30 | 3:13:30 PM - [ALWAYS ] - FlowStat:getHarvesterData(): data: HarvesterData [currentFlowRate=0, droppedFlows=15712567213, droppedPackets=175622664, mapFailures=15712567213, parseFailures=0, noFlowsFound=175622664, headerFailures=0, routerReboots=0]
Note that the screenshot does show non-zero data for 'discarded packets' and 'no flows found' on this harvester.
No routers were found to be in the rebootrefresh state. Data is displayed for devices sending flow to this router. Only the flow rates displayed here appear to be affected.
Release : 20.2
Component : NQRPTA - REPORTERANALYZER
Cause has not yet been identified.
The issue is resolved by restarting the harvester services.