Hi there,
This can happen for a couple reasons:
1) A PLUGIN CONFLICT
Most likely this is a conflict with another plugin. Please try disabling ALL other plugins. If the problem is then resolved, re-enable each plugin one at a time until you encounter the problem again. Let us know which plugin is causing the conflict and we’ll try to reproduce the problem on our end and find a workaround.
If after you disable ALL other plugins the problem is STILL there, change to the twentyfifteen theme and test. If the problem goes away at that point, we know it’s a problem with your theme. Email us your theme with a link via our contact form and we’ll see what we can discover about that.
2) AN API PROBLEM
I see you mentioned that you created the API key recently, but very often the keys are not configured correctly. Please review this article on how to properly configure your API key.
Let me know how that goes for you. If it’s still not working correctly after those two items, then please do the following:
1) Install the Send System Info plugin and provide me a link where I can see your system info (either the static link the plugin generates, or a link to download a .txt file)
2) Provide me a link to your website.
3) Provide a link to the business you are trying to use with our plugin.
Thanks!