We bought tickets on the Opodo website. On the website it was stated that the cancellation is free within 5 hours. Immediately after the purchase, we realized, that the connection between the flights was too short and we wanted to cancel the booking. First we tried to cancel via the website, it's says that to cancel, please call by phone. It was not possible to cancel by phone, because our reservation was not in the system and there is no way to connect to an agent without a valid reservation number. We tried to use the company's chat on the website, and after a long wait we were just thrown out of it. We wrote an email that we wanted to cancel the reservation. We just got an auto-reply for our letter. There was no other answer. That is, the company deprives you of any opportunity to use their free cancellation condition.
The next day I was able to reach the support over the phone, but all they can offer is to a change for 400 EUR or a non-refundable cancellation. They also offered to write a support case, but there's no answer since several days. They don't want to solve the problem and fulfill their own conditions. I have no choice but to assume a deliberate deception.
If you don't want to be tricked for you own money, don't get in touch with Opodo.
P.S. We have screenshots of their cancellation promises, refusal to cancel via web-site, phone call logs, etc.