The sponsored post by vodka brand Absolut featured a video of a group of young people sitting in a boat and had on-screen text, which read “enjoy Absolut responsibly”.
The complaint challenged whether the ad breached the CAP code because it featured people who appeared to be under 25.
Absolut said all the individuals featured were aged over 25 and had provided copies of their identification as proof.
The vodka brand also said it recognised that whether an individual “appeared” to be under 25 was a subjective area and it confirmed that it was not the company's intention to portray them as such.
It said the use of mobile phones for recording was a widespread activity across all generations and not prevalent with solely under-25s.
The advertising watchdog ruled that the ad must not appear again in its current form and it told Absolut to ensure that its ads did not feature people who looked under 25 in a significant role.
ASA noted that all of the individuals in the advert were shown dancing and using their mobile phones to record the experience.
It acknowledged that the individuals were all 25 years old or older, it nonetheless considered that some of the people would be considered to be under the age of 25 by some consumers.
A spokesperson for Pernod Ricard UK said: “As a producer, we are committed to responsible advertising and we work closely with organisations such as the Portman Group, Drinkaware and CAP in the development of both campaign materials and products, and to run regular training programmes for our employees.
“We respect the ASA’s ruling and, of course, will not feature this advert again. However, we are disappointed this complaint was upheld, given ASA acknowledged that, all of the individuals featured were over the age of 25 and we provided identification documents accordingly.
“Whether an individual ‘appears’ to be under the age of 25 is a very subjective thing.”