PlayStation TV is no longer available in Japan.
A NeoGAF commenter noticed the device - which enables you play PlayStation Vita games on your TV - has been discontinued on the official Japanese product page.
The device remains on sale across other territories.
Sony has yet to officially comment on the development, but we have reached out and will update you as and when we receive a response.
In our 2014 PlayStation TV review, we said "as a Remote Play extender for PlayStation 4 owners with fully wired homes or truly outstanding Wi-Fi connections, the PlayStation TV has definite value, and it's much easier than hauling your PS4 around the house and a lot cheaper than buying a second one. But as a standalone device, the PlayStation TV disappoints due to huge gaps in the game compatibility list and missing video apps, as well as poor PlayStation Now performance over Wi-Fi."