Walmart Cancels SNES Classic Edition Preorders

After listing the Super NES Classic Edition as available for preorder over the weekend, Walmart has been emailing customers to inform them their preorders have been cancelled.
In an email sent out to those who preordered, including a number of IGN employees, a representative for Walmart explained that "due to a technical glitch," the SNES Classic was made available on Friday, July 21 and the orders must now be cancelled.
The full email to customers reads:
Thank you for your interest in the Super