Google key API its giving error and its not defined

Dears developers. We are trying to put our website live.

But we getting this error( UNCAUGHT ERROR: GOOGLE IS NOT DEFINED). THE API . key is good.

The support of google says they dont support PHP platforms.

So seems the problem is that the key is good but maybe during the transfe of the website to another hosting, the API key can be misplaced.

So where/ and how can be fixxed?

Thank you.