So i've pre-ordered the new MK and it seems that i cant go online, any advice?
Also, have you connected your switch to the wifi in the settings of the switch itself?
From outside the game, in the main menu of your switch screen. Youcan also do an internet connection test from there to see if tghat's what's preventing you from connecting to the internet.
Here's how to find those options...
1) From the main menu of the switch console, if you go to "System Settings" (the little grey icon that is in the shape of a sun)
2) On the left-hand side there is a menu of options, scroll down a bit and click on the one that says "Internet"
3) Now on the right-hand side there will be an option that says "Internet Settings" (click on that)
4) when clicked on, if you are not connected to the internet it will come up with a little message that says "searching for networks" and will display a list of wifi networks nearby that you can connect to. (shown under the title that says "Networks Found")
5) Select the wifi network that you want to connect to, and enter the password.
6) It will now try to connect to it, and if successful your switch should now be able to always connect to that wifi connection. (notice how after it does this, there is now an option underneath the word "Internet Settings" that says "Test Connection". You can test it from there anytime to see if it is connecting properly.
Once you've done all that and are sure your wifi is connected, try going back into mariokart and go into the online multiplayer mode. If all was well with the above steps, it should now let you.
Hope this helps.