My iPad doesn't show the green button in wifi s...

My iPad Air 2 doesn't show the green button in wifi settings, it looks frozen.

I already tried everything I found related to wifi and iPads. Only one person asked (plus 6 more with the same problem) for help with: "green button in iPad wifi settings doesn't slide" ... unfortunately nobody has replied.

If anyone knows how to fix this, please reply as soon as possible.