Google update 22.06.2016 requires API keys to be used from now on. For more information please read this post – https://googlegeodevelopers.blogspot.com.by/2016/06/building-for-scale-updates-to-google.html

It’s a Google requirement. You simply need to input an API key for your Site Google Maps widget and it’ll work 100% as desired. To create an API key please navigate to this page – https://developers.google.com/maps/documentation/javascript/get-api-key and press the blue “Get a Key” button and follow the prompts.

EXAMPLE

Change this <!--GOOLE MAP--> <script type="text/javascript" src="http://maps.google.com/maps/api/js?sensor=false"></script> To this <!--GOOLE MAP--> <script type="text/javascript" src="https://maps.googleapis.com/maps/api/js?key=YOUR-API-KEY" ></script>