Do you mean the address search box on the Google Map field? I’ve attached a screenshot for your reference. If that is what you were talking about, it’s possible that there’s conflict on your site. In this case, could you please try to reproduce the issue on one of the WordPress’ stock themes (like Twenty Sixteen) with other plugins deactivated? If it disappears, then you can activate the theme and plugins one by one to see which one causes the issue.
Also, could you please check the Console tab of the developer tools in your browser for any error messages on the page?
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