To make the default country, find the file /root/app/helpers.php Line number 332

In the function oIsoCode() remove the below code

        $geoIp = oGeoLocation();
        if (! empty($geoIp->iso_code)){
            return strtolower($geoIp->iso_code);

You will get there only line return 'us';

Return the us to your country iso two digit code, then it will make it your default country.

Best regards