No way to enter reference number for tax repayment

I have received an assessment notice asking for income tax relief to be repaid via the HMRC website (no payment details are given). The letter states that I should use a specific reference number when making the payment, but none of the options to pay via the Self Assessment section of the HMRC website allow a reference number to be added. Should I just make the payment to HMRC Shipley via my bank and add the reference number that way? Thank you

Hi
Please refer here Pay your Self Assessment tax bill