I first heard of this a couple of months ago, but recently I have seen more reports of this occuring. Basically it seems that Ryanair are using cookies on your machine to keep the cost of your flights high.
You can check the cost of a flight on a Monday for example, check again on the Tuesday and the price will be the same or higher. However if you clear you cookies before checking the costs the price may of gone down. So if you do need to check the costs of your flight then you should clear your cookies first.
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