An advertising campaign run by KP Snacks and The Hundred has been banned for targeting junk food at children.
An email sent to an England and Wales Cricket Board (ECB) mailing list and a KP Instagram advert with the chance to win tickets were found to have breached the advertising watchdog's code.
The ECB said it was "sorry" an "error" meant the email was sent to under-16s.
The watchdog said not enough care was taken to ensure the Instagram advert was not directed at children.
The sponsorship by food brand KP Snacks of The Hundred, a tournament aimed at children and families, was criticised prior to its inaugural season last year.
"We told The England and Wales Cricket Board Ltd and KP Snacks Ltd to take reasonable steps in future to ensure that HFSS [foods high in fat, salt and sugar] product ads were not directed at children through the selection of media or the context in which they appeared," the Advertising Standards Authority added.
The ASA received two complaints, from the Children's Food Campaign and Food Active, and said there were breaches in two elements but not on five further Instagram posts and a website.
The email banned by the ASA contained the logos of The Hundred and KP brand McCoys and carried the text "we've teamed up with McCoy's, Official Team Partner of the Manchester Originals, to offer you the opportunity to claim a free bat and ball to celebrate The Hundred".
The advert was sent to an ECB list of 29,276 ticket buyers and those who had opted to receive ECB marketing, 326 of which were under the age of 16.
"We are sorry that due to an internal error an email promoting a giveaway of free cricket bats and balls was sent to a number of under 16s as well as the adults it was intended to be sent to," the ECB said.
"While the email contained a logo of one of our partner's brands, applicants were not required or encouraged to buy any products in order to apply for the bat and ball and the purpose of the competition was to get more people active. We are putting in place additional systems to ensure it does not happen again."
The post on Butterkist UK's Instagram account, another KP Snacks brand, advertised popcorn with the caption "WIN tickets to watch a sweet cricket game with Birmingham Phoenix in Birmingham this summer".
The ASA said the ECB and KP Snacks had not taken sufficient steps to ensure it was not directed at children, as it had with other adverts.
"At KP Snacks we recognise that as a responsible food manufacturer we have an important role to play in helping people make informed choices and enjoy our products responsibly," KP Snacks said.
"Our partnership with The Hundred enables us to introduce the game to new audiences and the Everyone In campaign is based around inspiring more people to get active.
"We welcome the ASA ruling and we will be working closely with the ECB to take on board the recommendations."