Viewport Settings.

I have an SEO analyzer telling me that Viewport should be set:

WARNING user-scalable in viewport should be set to ‘yes’
WARNING maximum-scale in viewport should not be set

And here is what they say is set.

viewport width=device-width, initial-scale=1, minimum-scale=1, maximum-scale=1, user-scalable=no

First I can’t seem to find this code. Second I don’t know if or how to change it.