A shopper has complained that she has been unable to buy sanitary products from a supermarket due to a ban on the sale of non-essential items.
In an exchange with a woman on Twitter, Tesco said it had been “told by the Welsh Government not to sell these items” during the firebreak lockdown.
Tesco has since deleted its tweet and apologised after the Welsh Government said its advice was wrong.
It comes as ministers are set to review the controversial policy.
Supermarkets have been told to close parts of their stores that sell items such as clothes, bedding and toys during Wales’ firebreak lockdown.
The policy has been criticised in a petition signed by more than 60,000 people.
In a tweet that was later deleted, Tesco responded by saying it had been told not to sell the items during the lockdown.
“This is wrong – period products are essential,” the Welsh Government tweeted in response.
“Supermarkets can still sell items that can be sold in pharmacies. Only selling essential items during firebreak is to discourage spending more time than necessary in shops. It should not stop you accessing items that you need.”
On Sunday, First Minister Mark Drakeford said implementation of the rule may be tweaked, but it would not be reversed.
The petition is now the largest ever submitted to the Senedd.
Mr Drakeford said a review into how the rules have been implemented would be held on Monday.
Secretary of State for Wales Simon Hart has urged Mr Drakeford to “scrap the policy” while Welsh Conservative leader Paul Davies called for Members of the Senedd to be recalled “virtually” to debate the matter.
“This is absolute madness by the Welsh Government, preventing people from buying the products which they want to buy,” he said.
Plaid Cymru health spokesman Rhun ap Iorwerth said the Welsh Government needed to change the way it communicated with businesses to help them plan.
In an interview with BBC Wales, Mr Drakeford said: “The position we face in Wales is really and deeply serious and for these two weeks we are asking people to stay at home and not to mix with other people as much as they can.
“If the rules are not sensible rules, if there are anomalies that are emerging, we will put them right, but the basic underlying public health emergency has not gone away.
“The basic decision is the right one. If the implementation of it, the interpretation of it needs to be revisited to make sure the rules are sensible, then we will do that.”
Tim Batcup, who has had to close his Swansea book shop during the lockdown, said the Welsh Government had made the “right call”.
But he said that while some supermarkets had stopped selling books, others were still selling them, and the messaging was a “bit mixed”.
“I don’t really understand the fuss… I don’t know why people can’t go a couple of weeks without a pair or pants or a candle,” he told BBC Radio Wales Breakfast.
“I think it’s a sincere attempt at levelling up, how effective it will be I don’t know. It might drive people towards the online giants, but they all seem to clean up anyway.
Nicky Small, who has had to close her craft shop in Llandudno, said she believed wool and other craft items were essential as the hobbies were helping many through the pandemic.
“I think there’s a balance, what is one person’s non-essential could be another person’s essential,” she said.
“The difficulty is anybody trying to dictate what essential is, because that will depend on who you are, what you are needing to get, if you have been waiting for payday.”
Head of the Welsh Retail Consortium, Sara Jones, said the rules were confusing, and banning people from buying certain items set a dangerous precedent.
“I think this policy is the wrong way to go about it, because rather than levelling the playing field, it’s just creating winners and losers, it’s pushing people online,” she said.
She said allowing an element of discretion would go against the purpose of the policy, as people would have to approach staff for items and spend more time in store.
“It’s distorting competition, which I think is setting a bit of a dangerous precedent,” she said.