There’s a requirement for using Google Maps and other Geolocation features in our websites. Since June 22, 2016 we need to have a Google Maps API Key to be able to use these features. At this moment, there’s a free plan that should be good for most of the websites, but if you get a (really!) large number of visitors you may need to subscribe a premium plan. You can read more about this here https://cloud.google.com/maps-platform/pricing/.
The small video tutorial above will show you all the steps that you need to follow. To access the Google Maps API Key console please follow this link (you need to have/create a Google account): http://bit.ly/2cqxWDc.
After generating this key and if you are using one of my themes, please go to the Contact Page tab of the theme options to place your API Key. If you are using another WordPress Theme or even a different CMS system, please get in touch with the developer to know where you should place your API Key.