Misleading information

I had booked for accommodation for December 2015 and i had paid a deposit of R800 . i Called them on the 06/11/2015 to cancel my booking and according to their cancellation policy if you cancel 21 days or more before arrival you will be deducted 30% of your deposit and according to my understanding they should debit R240. They later responded to my request on the 8/11/2015 informing me that they will be depositing R400 into my according and i i forfeited 50% of my deposit and i asked them why and no respond was given . Today 13/11/2015 i requested them to pay back my deposit and they inform me that they will pay back R350 into my account . I fail to understand why they do not want to pay back my money as i dont have a problem with them taking out the 30% but it seems like each and every time they decreasing the money due to me with no respond.