Opodo complaint: Cancelling my tickets without refunding

I bought two sets of tickets from London to Toronto via this terrible agent on 20 October (Booking Ref : 8157746139). On 1 December, I wanted to change the departure port to Birmingham, but I could not be connected to any human agent in Opodo. I thought I could try to cancel the tickets and re-book, on the normal assumption that if they did not allow for refund, they would not allow me to cancel, as I did not ask to forfeit my tickets ! They started to cancel my tickets the next day, but on their app, my tickets status is ed, even 5 minutes before I typed this complaint. I actually clicked their option of I cancelled my tickets by accidents 3 times after 2 December, with no response from them ! I called the airline company just now and they said the tickets had already been cancelled on 2 December, and I could not fly with them, and I could only take it to Opodo for refund matters. I got numerous emails from Opodo saying that my tickets were not refundable, so no refund. Basically, I paid 1500 pounds for NOTHING ! This is absolutely fradualent ! Imagine if you made a reservation for dinner and paid in advance, and if you don’t want the reservation later on, you can ask for a cancellation, but if your contract with them says no refund, you can still opt to eat there as you have PAID already ! I lost both my money and tickets ! All I want now is my tickets back or some forms of flight credits for future travelling. This is outright robbing !