Northern Ireland is the only part of the UK where supermarkets do not have access to a database which would enable them to offer the elderly and vulnerable priority online delivery slots.
The situation means that some of the most vulnerable here are being disadvantaged in comparison to those elsewhere in the UK - more than a month since the lockdown started.
Vulnerable and elderly people here are missing out as they cannot leave their home because Stormont has been unable to get a workable database to supermarkets, the News Letter newspaper reported yesterday.
As demand for online delivery slots increased, many people could not book deliveries due to the unprecedented levels of demand on supermarkets.
In response, supermarkets in England were given access to a database of the elderly and vulnerable by the government in London.
The devolved administrations - Cardiff, Edinburgh and Stormont - could not act as quickly because their systems are different to that used in England.
However, while the Scottish and Welsh governments have now brought themselves into line with England, Northern Ireland has not.
A number of supermarkets have been able to use some of their own data to prioritise the vulnerable, but it is far less complete than government data.
Last week, Sainsbury's chief executive Mike Coupe wrote to customers outlining the varying positions across the UK.
"We continue to prioritise elderly and vulnerable customers for online delivery and have offered over 725,000 elderly and vulnerable people access to slots so far," he explained.
"We identified 450,000 of these customers based on our own data and from customers registering with us."
He continued: "We have also been able to match over 275,000 additional customers in England, Scotland and Wales based on government data and we are contacting these customers to arrange priority home delivery.
"We will be in touch with more customers based on the database we receive from Northern Ireland as soon as we can."
Meanwhile, Stormont Communities Minister Deirdre Hargey has implemented a scheme which sees food deliveries made to the most vulnerable here.
Her department explained in a statement that progress is being made to ensure supermarkets will receive data information "as soon as possible", stressing that a number of data security measures have to be put in place before the information can be provided to retailers.