They sold my ticket

I was at the check in counter at 17h30 for my 18h10 flight. I know you sold my ticket at a high price to somebody else. Your employees behind the counter are trying to call through but nobody is answering. They send us from pillar to post. Even after purchasing another very expensive ticket I was so sent back and forth by your staff. Your service stinks. How can you close the check in 45mins before departure. And then you do nothing to help your customers. Your tactics to ****** money from the public is clear. If you close the check in early you can sell lost tickets much higher. Those that miss their flights will also have to buy new ones at very high prices. This is why your website and tickets don't say what time the check in actually closes. I want my money back. I'll be following this up on Facebook.