Ryanair has been told off by the British industry regulator for not making travel restrictions clear in a promotion for three million free tickets.
The budget airline's national press advert breached the code's rules relating to truthfulness, the Advertising Standard Authority said.
Its offer of "three million £0 tickets - just pay your taxes and charges" did not apply to flights on Fridays or at certain times on other days.
But the advert failed to make this clear, with small print stating only that the offer "... excludes travel for major sporting events and holiday periods".
The offer was only available on flights between noon on Mondays and noon on Thursdays and only after midday on Saturdays.
It did not apply on Fridays.
"We concluded that the ad was misleading and told Ryanair to make clear all significant exclusions to offers in the small print of future advertising," after an investigation, the ASA said.
Ryanair said the advert was not misleading because it made clear that the offer excluded major sporting events and holiday periods.
The advert also directed customers to the airline's website, where all the terms and exclusions were explained, the airline said.
Around 98% of Ryanair bookings are made online, the company added