WhatsApp is dropping support for Windows phones this year, and the mobile app may disappear from the Microsoft Store as soon as next month. Indeed, the company has quietly updated an online FAQ to mention that “WhatsApp may not be available in the Microsoft Store after July 1, 2019” (via All About Windows Phone).
In case you missed it, the app will stop working on Windows Phone and Windows 10 Mobile after December 31, 2019. The wording on the FAQ is pretty vague, but if you really want to keep using WhatsApp on your Windows Phone until the end, you should make sure to get it from the Microsoft Store before July 1.
In a general statement regarding unsupported platforms, the Facebook-owned company also says that “because we no longer actively develop for these operating systems, some features might stop functioning at any time.” WhatsApp will also stop working after February 1, 2020 on Android versions 2.3.7 and older and iOS 7 and older, so it's not just Windows Phone users that are being shown the door.