Contact Form 7 -> Paypal. need help with error.

I’m trying to do a simple data pass with a donate form using Contact Form 7 plugin data from 1 radio button to the paypal, donation, pay by credit card page. This is the code I’m using in the Contact Form 7 form….

[radio PRICE use_label_element "25" "50" "100" "Other"]?????????????[submit "Continue"]

This is the code I am using on the bottom of the actual donation page…

<script>
    function my_redirect() {
        var donate = document.getElementById('PRICE');
               if (donate == 'other')
                    {  var url = 'https://www.google.com';
                           window.location = url;
                    }
        var url = 'https://www.paypal.com/us/cgi-bin/webscr?cmd=_donations&[email protected]&item_name=Donation&currency_code=USD&amount='+donate+'';
        window.location = url;
}
</script>

This is what I get when submitting the form no matter the selection…
Screenshot

If I just copy/paste the var url into my browers “https://www.paypal.com/us/cgi-bin/webscr?cmd=_donations&[email protected]&item_name=Donation&currency_code=USD&amount=50” putting any value for the price, it works fine. But through the form it gives that error.

Also the other part is, why is my if statement not actually working? I just want it to forward to another url, but if they select other, nothing happens.

Thanks for any help.