OpenAI’s ad service has been serving ads after buyers paused their campaigns and charging them, according to a report. OpenAI began testing ad sales in ChatGPT in the US in February and expanded the service to the United Kingdom, Mexico, Brazil, Japan, and South Korea as of Tuesday. Ed Bolton, managing director of UK-based Excel4Business, told The Register his company encountered "an odd billing practice" while running campaigns in the US and Canada, noticing ads were delivered overnight on paused campaigns. An OpenAI support specialist initially acknowledged the failure, stating the campaign was marked as paused but the ad-level status did not refresh promptly, and that the Ads Engineering team had escalated the defect. The support reply confirmed £60.72 in invalid charges from the original occurrence and approximately £6.47 from the August 4–5 recurrence, with reconciliation extended to activity reported on August 6. However, several days later, OpenAI’s support rep reversed the prior determination and declined any refund or credit, citing the company's Advertising Terms, which state that ads may continue running even after a customer cancels a campaign and the advertiser still has to pay.