Yes, you can reset the Wifi configuration of Jooki, by performing a Jooki factory reset.
Warning: A factory reset will delete all music and settings (WiFi, Spotify, parental preferences etc) on Jooki's internal storage.
You will lose your uploaded music, playlists and custom token names, unless an SD card was in Jooki.
Here's how you do a factory reset:
Beside resetting wifi, a factory reset is also helpfull in other situations. If you'd like to know the other cases where a Jooki factory reset will be help full, click here