https://www.gamespot.com/articles/wii-shop-channel-is-closing-down/1100-6453682/

It's with a heavy heart that we have to tell you that the Wii Shop Channel will be shutting down on January 31, 2019. Users will no longer be able to add Wii Points to their account from March 26, 2018.

Thankfully, it will still be possible to re-download purchased WiiWare and Virtual Console titles, then transfer them to the Wii U using the Wii System Transfer feature, but Nintendo notes that this functionality will also cease to work in 2019, so get it done sooner rather than later. Nintendo has said it will provide exact timing on when redownloads will be disabled in the future.