As of today, it is no longer possible to add points to the Wii Shop Channel using either a credit card or Nintendo Points Card. Any points added before that date can be used to purchase content on the Wii Shop Channel until January 30, 2019.
On January 30th, 2019, Nintendo will close the Wii Shop Channel, which has been available on Wii systems since December 2006.
Now that customers have shifted to Nintendo eShop on Nintendo Switch and Nintendo 3DS, Nintendo plans to focus their efforts in those areas. It should be noted that content downloaded on the Wii Shop Channel can be transferred to a Wii U system using the Wii System Transfer Tool.
In the future, Nintendo will be closing all services related to the Wii Shop Channel, including redownloading purchased WiiWare, Virtual Console titles, and Wii Channel, as well as Wii System Transfer Tool, which transfers data from Wii to the Wii U system.
After January 30th, 2019 it will no longer be possible to purchase content from the Wii Shop Channel. Refunds of Wii Points are not possible and it should also be noted that Wii Points cannot be used to fund a Nintendo eShop account or Nintendo Account.
If you have Wii Points to spend, content you want to re-download, or content you’d like to transfer from a Wii system to a Wii U system, it is recommended you do so while the services are still available.