Imran Rahman-Jones
Technology reporter
Some Morrisons customers have still not had their Christmas orders after the supermarket experienced what it called "systems issues" on Monday.
One customer told the BBC she was waiting for about £200 worth of groceries, another said he was struggling to get answers from the firm.
It follows chaotic scenes at what is the UK's fifth biggest supermarket on 23 December - the biggest grocery shopping day of the year - which saw deliveries cancelled and promotional discounts not applied.
Morrisons has apologised and insisted deliveries are back to normal but it has yet to reveal the cause of the problems despite repeated requests from the BBC.
'In limbo'
One Morrisons customer in Worcestershire, who did not want to be named, pays for a delivery pass which gives her priority access to busy slots such as at Christmas.
An hour before her delivery slot on Monday evening, she received a text message saying the delivery had been delayed.
On Tuesday morning, she still had not heard anything from Morrisons and had not got the delivery.
"I have no idea if my order is coming or not," she tells BBC News. "So I'm kind of at a real loss."
The customer had an order worth about £200, and had saved vouchers over the year to take it down to £100.
She says the lack of communication has left her "in limbo."
"I could go [out] today and spend £200 and then come home and Morrison's turn up with £200-worth of shopping," she adds.
"The complete lack of communication is the biggest thing, because you can't form a plan B, and you can't plan when it's Christmas Eve."
Problems started early on Monday morning, when customers who had ordered for Christmas started receiving emails saying their deliveries would be delayed or cancelled.
Then, when shops opened, in-store customers found their vouchers were not being accepted at the tills.
In response, Morrisons applied a 10% discount for members of their More Card loyalty scheme and applied other discounts for non-More Card holders.
"Today the Morrisons store experience is back to normal, but all More Card customers will still get 10% off their whole shop instore throughout the day," the supermarket told BBC News on Tuesday morning.
It added: "Click and Collect and Home Deliveries are working as normal. We are determined not to let a single customer down this Christmas."
Another Morrisons customer, Matthew Welch in Northumberland, had his delivery cancelled yesterday morning.
He said the manager he spoke to when he phoned up was "less than helpful."
Matthew told BBC News: "The manager had said that he needed to wait until the problem was fixed and then he would come back to me, which he did not."
He added: "I have since discovered that another four people in the village where I live have also had their Christmas deliveries canceled yesterday as well."
The BBC spoke to two other people in Northumberland who had deliveries cancelled yesterday.
Morrisons insists these cancellations were separate to the main "systems issues" it had, but would not go into more detail.
Mr Welch ended up buying his groceries locally, but has not had any information regarding his Morrisons order.
"Especially with Christmas slots, you're booking them six to eight weeks in advance, and there's really no excuse to cancel on the day the delivery is due," he says.
"I'll be swapping to another supermarket, but I won't use Morrisons again for anything," he adds.
'Will not be forgotten'
Consumer expert Kate Hardcastle says the supermarket chain needs to be honest and transparent with its customers.
"It's something that will be not very quickly forgotten into the new year," she told the BBC.
"I think it's about trying to lean in, doing as much as they can, being very honest about it," she adds.
She says that the way supermarkets use loyalty schemes have changed in recent years, from offering points to offering discounts for members.
"If we're going to see retailers implement these systems where you can only access a certain price through the schemes, then you absolutely have to make sure they're watertight," she says.
"Our grocery stores, they are built on legacy IT systems which can really get impacted at sensitive times of year... it's about trying to understand into the new year how they can really work with their loyal customers to make up for this."