Teneo School - Withholding of Monies - Unacceptable behaviour from a School

My son left the school in 2022. However, there was an amount owing to me which was not refunded. So on 15 January 2023, I logged a ticket with the Accounts Dept to refund me my monies (reference number 70552). I have been following up every month with them & constantly receive the default response from the Accounts Dept: "The request is currently with the Financial Manager and will be processed soon". Over 6 months later & my monies are still not refunded. Is there a legal route or any other means for me to get my monies?