Microsoft appears to be running out of its inventory of Lumia 640 units in the U.S. The 5-inch smartphone is no longer available for sale from AT&T, the Microsoft Store site and other retailers.
Microsoft first announced the Lumia 640 in March 2015 and it went on sale in the U.S. in May of that year. Now it looks like the only major outlet in the country that is selling the phone is Cricket Wireless, which is selling the phone without a contract for $29.99.
While the Lumia 640 seems to be near the end of its retail life, its larger brother, the Lumia 640 XL, is still available on the U.S. Microsoft Store site, along with AT&T.
Thanks to Tom for the tip!