Tesco’s website and app are down for a second day after being hit by hackers.
Thousands of shoppers have been unable to book deliveries or amend existing orders due to the outage.
The grocer said it did not believe customer data would be impacted and work was being taken to ensure private information was protected.
A Tesco spokesperson said, “Since yesterday, we’ve been experiencing disruption to our online grocery website and app. An attempt was made to interfere with our systems which has caused problems with the search function on the site.
“We’re working hard to fully restore all services and apologise for the inconvenience. There is no reason to believe that this issue impacts customer data and we continue to take ongoing action to make sure all data stays safe.”
The site was still “experiencing disruption” on Sunday evening.
Shoppers have been complaining about the outage on social media and said they were expecting to be disappointed with their orders because they could not amend them in time.
The grocer said it was unable to amend customer slots and orders but could cancel orders and issue refunds.