Thank you GJC

but to be honest I didn't fully understand what you meant.
However, I really appreciate your help and the form is now fully working with the phone number appearing in the email received.
If anyone else needs this on their 'Ask A Question' this is working for me on Joomla 3.6.2, VM 3.0.9
It is now working with the following changes:1. Changed /public_html/components/com_virtuemart/views/askquestion/view.html.php
(See bold section)function renderMailLayout () {
$this->setLayout ('mail_html_question');
$this->comment = vRequest::getString ('comment');
$this->phone = vRequest::getString ('phone'); $this->user = JFactory::getUser ();
if (empty($this->user->id)) {
$fromMail = vRequest::getEmail ('email'); //is sanitized then
$fromName = vRequest::getVar ('name', ''); //is sanitized then
//$fromMail = str_replace (array('\'', '"', ',', '%', '*', '/', '\\', '?', '^', '`', '{', '}', '|', '~'), array(''), $fromMail);
$fromName = str_replace (array('\'', '"', ',', '%', '*', '/', '\\', '?', '^', '`', '{', '}', '|', '~'), array(''), $fromName);
$this->user->email = $fromMail;
$this->user->name = $fromName;
}
2. changed /public_html/templates/t3_blank/html/com_virtuemart/askquestion/form.php
(See bold section)<table class="askform">
<tr>
<td><label for="name"><?php echo vmText::_('COM_VIRTUEMART_USER_FORM_NAME') ?> : </label></td>
<td><input type="text" class="validate[required,minSize[3],maxSize[64]]" value="<?php echo $this->user->name ? $this->user->name : $askQuestionData['name'] ?>" name="name" id="name" size="30" validation="required name"/></td>
</tr>
<tr>
<td><label for="email"><?php echo vmText::_('COM_VIRTUEMART_USER_FORM_EMAIL') ?> : </label></td>
<td><input type="text" class="validate[required,custom[email]]" value="<?php echo $this->user->email ? $this->user->email : $askQuestionData['email'] ?>" name="email" id="email" size="30" validation="required email"/></td>
</tr>
<tr>
<td><label for="phone"><?php echo vmText::_('COM_VIRTUEMART_SHOPPER_FORM_PHONE') ?> : </label></td>
<td><input type="text" class="validate[required,minSize[8],maxSize[15]]" value="<?php echo $this->phone ? $this->phone : $askQuestionData['phone'] ?>" name="phone" id="name" size="30" validation="required phone"/></td>
</tr> <tr>
<td colspan="2"><label for="comment"><?php echo vmText::sprintf('COM_VIRTUEMART_ASK_COMMENT', $min, $max); ?></label></td>
</tr>
<tr>
<td colspan="2"><textarea title="<?php echo vmText::sprintf('COM_VIRTUEMART_ASK_COMMENT', $min, $max) ?>" class="validate[required,minSize[<?php echo $min ?>],maxSize[<?php echo $max ?>]] field" id="comment" name="comment" rows="8"><?php echo $askQuestionData['comment'] ?></textarea></td>
</tr>
</table>
3. changed /public_html/templates/t3_blank/html/com_virtuemart/askquestion/mail_html_question.php
(See bold section)<tr>
<td align="center" style="border-bottom : 1px solid #dad8d8;"> <span style="font-size: 14px; font-weight: bold"><?php echo vmText::sprintf('COM_VIRTUEMART_QUESTION_MAIL_FROM', $this->user->name, $this->user->email); ?></span>
<br /><br /><?php echo $this->phone; ?><br /><br /> <br /><br /><?php echo $this->comment; ?><br /><br />
</td>
</tr>
4. changed /public_html/templates/t3_blank/html/com_virtuemart/askquestion/mail_raw_question.php
<?php
defined('_JEXEC') or die('');
echo vmText::sprintf('COM_VIRTUEMART_WELCOME_VENDOR', $this->vendor->vendor_store_name) . "\n" . "\n";
echo vmText::_('COM_VIRTUEMART_QUESTION_ABOUT') . ' '. $this->product->product_name;
if ($this->product->product_sku) echo vmText::_('COM_VIRTUEMART_PRODUCT_SKU').' '.$this->product->product_sku .')' ;
echo "\n" . "\n";
echo vmText::sprintf('COM_VIRTUEMART_QUESTION_MAIL_FROM', $this->user->name, $this->user->email) . "\n";
echo $this->phone. "\n";echo $this->comment. "\n";
--------------------------------------------------------
It's working for me.
Thanks again GJC for you valued input.
