Bad service!

Booked via head office for 2 nights at the Cabanas, on the day of booking in we got told that head office overcharged for the 2 nights stay for 2 rooms and that we only need to pay half price, we double checked with her twice before eventually paying. We spent the 2 days and on the day we booked out they told us we still owe money for the second nights stay. We eventually compromised and said we would pay half of the outstanding amount as it was not our fault that the staff made an incorrect booking and charged us incorrectly. A week later we are being harassed for the rest of the money. It was THEIR MISTAKE , not ours. Extremely bad customer service.