complaint Imagine Cruising

We were very excited and booked a cruise by telephone. All the adverts say that all flights and taxes are included. The agent read out reams and conditions and in all that I really did not take it is that he had said that flights were not included. However when we asked about them booking our flight we were told that the agent had told us that the flights were excluded. We were extremely upset as this would make the trip very expensive. We asked for a copy of the tape and the agent did say the flights were excluded. We wanted to cancel, nearly a year ahead, and were told that we would then lose our R20,000 deposit. We asked if there was any way round this as R20,000 a year ahead was extreme. They said we could change the dates of our trip. However when I enquired about doing just that I was told that there was not another of the same trips in 2019. I have since seen adverts for almost the same trip. We were going to go ahead as it was too much to lose. However the flights took the price way out of our price range. Is there any way to get some of our deposit back if we now cancel our trip? Thank you very much.