Hidden type input values not being passed in php

Question

I have a contact form that does a very simple captcha system such as "Is the sun hot or cold?" And the user enters hot. I include the original question and answer to the following processing form in type="hidden" fields.

The problem is that these input fields are always blank on the following php page. Here is my code on the contact form:

<form id="contact-form" name="contact-form" method="POST" onsubmit="return true;" action="submit.php">
    <fieldset>
        [...]Removed For Convenience[...]
        <label class="captcha" id="captcha" name="captcha">
            <span style="color:#FFFFFF">Is the sun hot or cold?</span>
            <input type="text" value="hot" name="answer" id="answer">
            <input type="hidden" value="Is the sun hot or cold?" name="realquestion" id="realquestion">
                <input type="hidden" value="hot" name="realanswer" id="realanswer">
            <p>Please answer as simply as possible; hot, cold, z, etc. (This question is for security purposes)</p>
        </label><br>
    <div class="clear-form"></div>
        <div class="buttons-wrapper">
            <input id="button-2" type="submit" value="Submit">
        </div>
    </fieldset>
</form>

And the following page, submit.php I put this at the very top "print_r($_POST);" and this is the array that was returned:

Array ( [Name] => asasasas [Email] => [email protected] [contactTime] => Best Time To Contact You? [Phone] => Phone: [Account] => Account: [OS] => [Department] => [Message] => Message: [answer] => hot [realquestion] => [realanswer] => ) 

Now the kicker, if on my contact page I change type="hidden" to type="text" for these two fields and nothing else the code will work. Once that has been done I can change it back to type="hidden" and it will continue working for that session. If I switch browsers, restart the browser, or go to a different computer it will go back to not being able to read those hidden input fields.

Has anyone come across this before or know what might be happening? I'm at a loss. I would really like to figure out this problem and not use a workaround like javascript validation, I am already doing that but I want the php check in place in case they have javascript off (I am assuming the bot spam we have been getting has it off).

Answer 1

Problem was solved by changing

<input type="hidden" value="Is the sun hot or cold?" name="realquestion" id="realquestion">
            <input type="hidden" value="hot" name="realanswer" id="realanswer">

to

<input type="hidden" value="Is the sun hot or cold?" name="realquestion" id="realquestion" **/>**
            <input type="hidden" value="hot" name="realanswer" id="realanswer" **/>**

And not getting tripped up by browser caching.