TCM0042100 | Changes - miscellaneous (A-F): Change results in an underpayment (in-year) (Info)
From HM Revenue & Customs · Tax Credits Manual
An in-year underpayment of tax credits may result from a change of circumstances.
If the change is
not a reduction in the household income, the underpayment will be paid automatically by direct payment immediately to the customer.
a reduction in the household income, follow the guidance in TCM0234040.