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HMRC internal manual

Debt Management and Banking Manual

Pre-enforcement: coding out: class 2 NIC debts: taxpayers with other coded out debts

A taxpayer may also have coded out Self Assessment (SA) debts and Tax Credit (TC) overpayments.

DMBM618510 provides guidance on dealing with SA coded-out debt queries

DMBM618410 details the process for dealing with queries on coded out TC overpayments.