Hello, first thanks for your purchase.
A few months ago Google Maps made some changes in the usage of their API. Now it’s required you add your billing data to use the Google Maps. You can read more about that here:
https://cloud.google.com/maps-platform/pricing/
and here is an article with more explanation about that:
Basically you will receive an credit of $200 each month to use the google services for “free”, but for that is required you add your billing information. If your website has low traffic/visits per month, probably these $200 in credit will be sufficient. For example, our Porto preview website has high volume of traffic/visits and these $200 is sufficient.
We hope this helps!
Please try that and let us know if you need further assistance.
Kind Regards,
Rodrigo.
If you are satisfied with Porto HTML and our support, please leave your comment and rating on ThemeForest downloads page. That helps us a lot: https://themeforest.net/downloads