Adverts for Walkers Spell and Go holiday competition have been rapped by the Advertising Standards Authority (ASA), after it received 112 complaints.

The ASA ruled the adverts for the campaign - in which participants were required to spell out the name of destinations for an opportunity to win one of 20,000 holidays - were ”misleading and likely to cause unnecessary disappointment to consumers”.

The adverts ran throughout May 2016.

Walkers Snacks Ltd said that 20,000 holidays to 26 destinations were available to win. Shoppers were required to collect letters which they entered into a dashboard on the promotion’s website. Participants who were able to spell out the name of one of the destinations won a holiday there.

They could select a maximum of five letters to swap for others that were randomly generated. However, complainants believed some were withheld, with C, D and K never being offered.

Walkers said there were sufficient quantities of these letters in circulation.

The ASA noted the random swaps mechanism offered only certain letters, in spite of the promotion’s terms & conditions stating that “all letters are treated equally”.

Walkers later reconfigured the random swaps function to include all letters, but the ad watchdog considered the site’s original limitation was a “significant condition” and its omission from promotional material on the brand’s site “was misleading and likely to cause unnecessary disappointment to consumers”.

A spokeswoman for the snacks giant said: ”We welcome the ASA’s recognition that our Spell & Go promotion was fair as everyone who participated had an equal chance of winning one of the 20,000 holidays available. We appreciate that the online letter swapping mechanic could have been clearer and we will ensure all future promotions take this feedback on board.

”Our Spell & Go promotion has been very popular and we’ve given 796 families, 4 star, seven-night holidays worth over £1.35million. Also, so far over 8,000 people who took part in the promotion have won instant prizes including sunglasses, books and cameras.

”We’re aware some customers are disappointed that they haven’t been successful in winning a holiday. 20,000 holidays could have been won if all the promotional packs in the market had been played and we would have honoured all of those should that have been the case.”

The ASA also investigated, but did not uphold, complaints that some promotional packs of Walkers crisps had incomplete or invalid competition codes or no code at all.