Amazon has fallen foul of the Advertising Standard Authority (ASA), with the watchdog due to warn the e-commerce giant that it must clarify that some items on its Prime service are not eligible for next-day delivery.
According to a ruling due to be published next week, the ASA has ruled that Amazon has been "misleading" consumers by promoting one-day delivery as part of its premium Prime subscription service.
The ruling, seen by the Time, came after 270 people complained at not having received their delivery by the following day.
The company’s ads "must not appear again in its current form” as a result.
“Because consumers were likely to understand that, so long as they did not order too late or for Sunday delivery, all Prime labelled items would be available for delivery the next day with the One Day Delivery option,” said the ASA.
An Amazon spokesperson said: "Amazon Prime offers fantastic benefits to members including One-Day Delivery on millions of eligible items at no extra cost.
"The expected delivery date is shown before an order is placed and throughout the shopping journey and we work relentlessly to meet this date. The overwhelming majority of One-Day Delivery orders are delivered when promised.
"A small proportion of orders missed the delivery promise last year during a period of extreme weather that impacted all carriers across the UK, and we provided support to impacted customers at the time."