New York CNN  —  Some of the United Kingdom’s largest supermarket chains are grappling with technical issues that have left customers without grocery deliveries and unable to make contactless payments. Sainsbury’s, which owns 600 grocery stores and 800 convenience locations across the country, said on Saturday that “an error with an overnight software update” has prevented the company from fulfilling “the vast majority” of grocery deliveries to customers. Sainsbury’s did not specify how many customers were affected. Online ordering is still operational and “customers can place a new order now for delivery any time from tomorrow,” the company told CNN. However, the technical glitch has also affected the contactless payment system across all of its locations. While stores remain open, Sainbury’s said customers must pay with either cash or a chipped credit card while the company works to resolve the issue. Tesco, the largest UK supermarket chain with more than 4,000 stores, said it is also working to fix “a technical issue which has meant we have had to cancel some online orders that were due for delivery today.” Tesco said it was sorry for the inconvenience. The malfunction only affected a small portion of orders, and impacted customers have not been charged. In-store shopping and placing online orders are not affected, Tesco said. These technical issues come just one day after McDonald’s was hit by a system failure that closed restaurants and disrupted online and app orders around the world, including in the United States, Australia, Japan, Hong Kong, and the United Kingdom. CNN’s Olesya Dmitracova, Anna Cooban, Juliana Liu and Michael Nam contributed to this reporting.