Bus Service Complain

When I was traveling in the USA I bought a bus ticket from Indianapolis to Cleveland at 7 p.m., 7 days before the trip. I thought that everything was OK and I did not worry about the time that I had to arrive in the bus station. When I arrived at the bus station I found a long bag`s line but at that time I didn't realize that it was a problem. I left my luggage int he line and just waited the bus. When the bus driver announced the departure, everybody went to the line and started to get on board. Suddenly, the bus driver stopped and said that nobody else could get on board because the bus was full. I couldn't believe in that because it never had happened with me before. So I went to the customer services and asked what time would depart the next bus and they said that it would be at midnight. I replied that I had bought a ticket to depart at 7 o' clock and they said that they couldn't do anything. So I back to the line and asked to another person, who also had lost the bus, how I could complain about that and she answered me that exist a number to call but nobody do it because nothing would happen to the company and it was a waste of time. After listened it I gave up to complain.