Google has launched a major update to the Maps API platform in 2018. Google changed it to premium plans. Based on this update, every Google API should have a valid API key and Google billing account.
You can get more information here:
https://cloud.google.com/maps-platform/user-guide/account-changes/
A new pay-as-you-go pricing plan went into effect for Maps, Routes, and Places. This new plan gives you more flexibility and control over how you use Google APIs. You can use as much or as little as you need and only pay for what you use each month.
You get a $200 credit per month and once that amount of API calls is used up, you'll start getting charged:
https://cloud.google.com/maps-platform/pricing/
If you are facing error messages on Google Maps, refer to this article that lists the types of errors and reasons.
https://developers.google.com/maps/documentation/javascript/error-messages
Since the Google Map API Key involves you setting up payment, we need your help to generate the API key. Follow the instructions provided in the link below to get an API key from Google:
https://www.wpgmaps.com/documentation/creating-a-google-maps-api-key/