Here’s a short piece you can use for a blog, news post, or update notice regarding Mario Kart 8 Deluxe update 3.0.5.
Ensure your Nintendo Switch is connected to a stable Wi-Fi or LAN connection.
Update 3.0.5 is widely considered the "final" update for the original Mario Kart 8 on the Wii U. It was released several months after the launch of the final DLC pack (Animal Crossing Cross-ing) and shortly before the official discontinuation of certain online services for older Nintendo titles.