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Depending on the date of your cruise, it is certainly possible to get the lower fare. Since you have an active booking with an agent you have to go through them. RCI won't talk to you if someone else has your reservation. Contact your agent and tell them what you found, and ask the agent to get the new price for you. A caveat here...if you already made your final payment and are in the penalty phase of your booking, it may not be possible to get the lower price - even if you cancel your current booking and try to re-book the same cruise with RCI directly.