Booking.com Corruption

Booking.com have been terrible in assisting my case as they know they were in the wrong after a guest had booked and had a party in the apartment they were due to check out in 5 or so hours and on the morning of check out they had told booking.com that they had not been accommodated and as a result the booking was cancelled. I then showed booking.com evidence of their stay and also damage to the apartment and booking.com have strung me along for almost three months now giving me excuses after excuses as to why they cannot payout the money I am owed. I am being pushed to my last resources where I feel I need to seek legal advice. I even received an email saying I would be receiving a payout in 7-10 days but I believe that was just to shut me up as low and behold almost two months later I have still not received anything and they have now gone back to their initial stance of not helping their partners and allowing customers to defraud their system. Who else has been in this situation?