[Contact-Form 7] Email Validation error shows up incorrectly

We use contact forms to allow our hiking club members to sign up for hikes. Each hike has its’ own form that ties to a specific event (date & time). This works like a charm.

We added the ability to filter a submission by the user-name, via the “Add Shortcodes Actions and Filters” Plug in. (We allow multiple users to share email addresses (ie husband and wife) – so need to check the sign up via user name. )

This works – however along with the message that a user is already logged in, I get a validation error message on the user name.

Here is the CFDB filter (via the plug in):

/**
 * @param $formName string
 * @param $fieldName string
 * @param $fieldValue string
 * @return bool
 */

function is_already_submitted($formName, $fieldName, $fieldValue) {
    require_once(ABSPATH . 'wp-content/plugins/contact-form-7-to-database-extension/CFDBFormIterator.php');
    $exp = new CFDBFormIterator();
    $atts = array();
    $atts['show'] = $fieldName;
    $atts['filter'] = "$fieldName=$fieldValue";
    $atts['unbuffered'] = 'true';
    $exp->export($formName, $atts);
    $found = false;
    while ($row = $exp->nextRow()) {
        $found = true;
    }
    return $found;
}

/**
 * @param $result WPCF7_Validation
 * @param $tag array
 * @return WPCF7_Validation
 */
function my_validate_email($result, $tag) {
    $formName = 'San Tan - Moonlight Trail (Short) - 2 Nov 2016'; // Change to name of the form containing this field
    $fieldName = 'your-name'; // Change to your form's unique field name
    $errorMessage = 'You have already registered for this hike.'; // Change to your error message
    $name = $tag['name'];
    if ($name == $fieldName) {
        if (is_already_submitted($formName, $fieldName, $_POST[$name])) {
            $result->invalidate($tag, $errorMessage);
        }
    }
    return $result;
}

// use the next line if your field is a **required text** field
add_filter('wpcf7_validate_text*', 'my_validate_email', 10, 2);

Questions:

1. How to stop the validation error from showing up when a user tries to register more than once?

2. If the filter is set to look a specific form name, why does it hit anytime someone tries to register for a hike? ie it will tell me I have already signed up for a hike when I haven’t.

Thanks for any thoughts and pointers.

Cheers