Mango Closes Flight Early

I had a flight with Mango airlines on 27th December 2015. This flight was booked months in advance. <br> Due to the queue being extremely long at check-in, I decided to have a cool drink and come back a bit later. I basically joined in behind the person I remember being at the back of the long queue. <br> When I got to the front, about five minutes before the flight would close for check-in, the attendant said the flight is already closed and I missed it. She then sent me to another check-in counter and they said the same. So after about twenty minutes of speaking to check-in attendants and looking for the customer services counter (which I was given wrong directions to by the second check-in attendant), I was told that they should have been able to check me in until ten minutes after the closing time. So I was there 15 minutes before the flight was really closed.<br> I have received no refund or any discount on new tickets.