On April 1, 2016, Nintendo announced in their “What’s New” blog that Nintendo DSi Shop services will be discontinued in the early months of 2017. Nintendo DSi Shop points will still be obtainable until September 30, 2016 while purchasing content will last until March 31, 2017. Additionally, Nintendo has stated that the ability to re-download DSi games from the shop will end at some point too. Nintendo has assured us that DSi Ware games will remain in the Nintendo eShop.
[Source: Nintendo’s “What’s New” Blog post]