How to make this function do nothing in Case::No?

I have a function contain 3 Cases, Yes,Request and No, I would the function to do nothing by choosing No case.

IF CONFIRM(ConfirmQst) THEN 
    CASE GeneralLedgerSetup."Address Data VAT" OF
      GeneralLedgerSetup."Address Data VAT"::Yes:
        PopulateFieldsFromVATRegLog(RecordRef,RecordVariant,VATRegistrationLog);
      GeneralLedgerSetup."Address Data VAT"::No:
       //What to write here ?
      GeneralLedgerSetup."Address Data VAT"::Request:
        IF HasAddress(VATRegistrationLog) THEN
          ConfirmQst := ValidVATNoQst
        ELSE
          IF CONFIRM (ValidVATNoNoAddressQst) THEN
            PopulateFieldsFromVATRegLog(RecordRef,RecordVariant,VATRegistrationLog);
          END;