Poor service

I booked via mytrip and my departure time stated 8.30 on my ticket and on the app. When I got to the airport I was told that the flight departed at 6.30. I have not received any communication of changes and had to purchase new ticket.it was a big inconvenience. I have had no help and being referred pillar to post.as a customer this is not my problem and I want my refund.between the airline and the agency something went wrong.why must I suffer as the customer. I need this sorted asap.