In under an hour, Walmart Canada sold out of its latest release of PlayStation 5 consoles, leaving many customers out of luck and complaining of “bots” buying out the device and various website issues.

The company said a limited quantity of Sony’s (SNE) next-generation consoles would be available on its site on Thursday for a brief period of time.

Walmart also said it would have a limited quantity of Microsoft’s (MSFT) next-generation console series available, but shortly after the PS5 sold out, Walmart Canada’s gaming-related Twitter account posted that it was “postponing” that release to tomorrow.

Many customers trying to get the PS5 were able to add a console to their cart, but were immediately told the product was sold out when trying to check out.

Use CAPTCHA so bots can’t buy: Wong

Jane Manchun Wong, a social media and website feature researcher, said in an interview that companies should find better ways to reduce the number of “bots” from purchasing products during flash sales or new product availabilities.

“[Companies can] find a way to reduce the automated bots from gaming the system. In other words, verify whether the customers are real,” she said. “A simple CAPTCHA mechanism can prevent bots from automatically buying up everything in a short amount of time.”

Another way that would probably make the experience more seamless, Wong said, would be for sites to offer an SMS confirmation.

“It’s not as easy to own a huge amount of phone numbers. That should add another speed bump on such automation,” she said.

Alternatively, for coveted products, Wong said it might make more sense for websites to put people on a waiting list.

“And on a set date and time, randomly pick a first batch of customers to proceed with the purchase,” she said.

Yahoo Finance Canada reached out to Walmart Canada for comment on website issues but did not get a response in time for publishing.

COVID-19 changed the way of buying coveted products: Lachman

Richard Lachman, an expert on tech user experience and associate professor at Ryerson University, said in an interview that COVID-19 has shifted the way many companies are selling coveted products and are simply not prepared for this new model.

“What retailers normally do is they would have a line up outside at Best Buy or Walmart for electronic devices. That’s how they would build up attention and they would have a limited quantity and people would camp out overnight,” he said.

“But now we’re shifting to online and it’s putting a strain on these retailers that they weren’t ready for.”

Lachman said companies should take inspiration from the sale of concert tickets.

“Maybe they release something at a particular time and then you have a spot in line and you have a limited amount of time to complete your transaction,” he said, adding that many concert sites ramp up server capacity to ensure site crashes don’t take place.

Lachman added that likely this was an oversight by Walmart not realizing and asking “this is going to be a limited demand item, is our system up to this?”