Some of Sainsbury's customers won't get their online food shop after the store experienced "technical difficulties".

Many of those affected have been contacted via text message, telephone or social media.

But some shoppers say deliveries are late and they don't know if they will turn up.

"We are experiencing a technical issue today that is affecting deliveries to a small number of online customers," a spokesperson told Newsbeat.

"We're contacting all those affected to apologise for the inconvenience this will cause them and to rearrange deliveries."

It's thought the majority of customers will receive their orders as planned and Sainsbury's says it is putting on extra delivery slots in the coming days.

Other customers whose deliveries have failed to arrive say they are having trouble getting through on customer service phone lines.

On social media, Sainsbury's has been telling customers refunds will also be available for deliveries that don't turn up.

Earlier this week, one online shopper criticised Sainsbury's for the number of plastic bags she received in her delivery.

Andrea Berry ordered 53 items and got sent 23 carrier bags.

She said that in one of the bags there was a lone mango and that the three packages of raw meat she ordered were double-bagged.

"Our drivers will also take back any unwanted bags," a spokesperson for Sainsbury's told Newsbeat.

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