SolvedTCM0152090 | Notes - recording and viewing: Standardised referencing
From HM Revenue & Customs · Tax Credits Manual
If the customer has not supplied sufficient information or referencing on their correspondence, the Customer Information Team (CIT) will need to identify through Household Notes where to redirect the correspondence.
To assist CIT with this action, the following standard reference must be applied to all standardised messages when adding to Household Notes on NTC.
CP NW & NE - ‘CP number/Grp Number/Task/Building/Floor or room/PID’
Compliance - ‘CxHx/PID/telephone number’