Error with DQS in SSIS again

Question

Hi All ,

the below error was encounter with DQS component in SSIS ,may i know what it describes ?

[DQS Cleansing] Error: An unexpected error occurred in the DQS infrastructure.
System.NullReferenceException: Object reference not set to an instance of an object.
   at Microsoft.Ssdqs.Component.DataCorrection.Logic.DataCorrectionComponent.ProcessChunk(ReadOnlyCollection`1 fieldMappings, ReadOnlyCollection`1 records, CorrectedRecordsStatusStatistics& correctedRecordsTotalStatusStatistics)