Booking.com £174 Refund Delayed for Cancelled Hotel Bookings

I am writing regarding two cancelled bookings made through Booking.com for stays in Leeds, for which I am still waiting for a total refund of £174. The first booking was for Quality Apartments, 320 York Road, Leeds LS9 9DN, originally booked for 23rd August and cancelled on 24th August. The second booking was for the Ibis hotel near the Royal Armouries in Leeds, originally booked for 28th September and cancelled on 2nd September. The booking reference for the apartment is 152138063974 and for the Ibis hotel it is 5580049645. The owner of the apartment has informed me by phone that Booking.com is holding the money that should be refunded to me. Despite both reservations being cancelled and 12 days having passed since the most recent cancellation, no refund has been returned to my account, and I have not received any explanation or email from Booking.com or the properties about this delay. I kindly request that the total amount of £174 for these two cancelled bookings be refunded to me as soon as possible.