I replied to your e-mail. Here is what I said:
Make sure you are using the same URL in both browsers. For example, domain.com and
www.domain.com require separate GoogleMaps API keys (you can enter up to 4 API keys in the plugin). Also check to verify the host names in the GoogleMaps plugin settings do not include the http:// prefix, since it is not needed.
If neither of those options work, you can send me the URL. Also, tell me the version of Zap Calendar and the GoogleMaps plugin you are using. Thanks.