I'm sorry; I'm an independent tech; you can try Nintendo support, but they may not help you or the network issue can be complicated for them to fix. You can always come back if you still need help; we guarantee our service, so don't worry.
Have you tried to disconnect the power cord(s) from your internet / wireless modem/router device(s) for a few minutes, then reconnect, and check?
; also, turn off the Wii, then disconnect power cord from it for a couple of minutes, then re-connect, then turn on and check.
When you connect the Wii to your Wi-Fi/wireless network name, it asks for password *****? Then after you enter the password, what does it say?
Is the Internet or any online game or any other Internet app currently working fine on the Wii?
Please let me know. Thank you.