You can solve it by adding a code that allows only the owner to change the email
From file
system/box/edit_profile.php
Search for
<?php if(isMember($data) && isSecure($data)){ ?>
<div onclick="getEmail();" class="listing_half_element blisting">
<div class="bcell_mid"><i class="fa fa-envelope proicon"></i><?php echo $lang['edit_email']; ?></div>
</div>
<div onclick="getPassword();" class="listing_half_element blisting">
<div class="bcell_mid"><i class="fa fa-key proicon"></i><?php echo $lang['change_password']; ?></div>
</div>
<?php } ?>
Replace it with this :
<?php if(boomAllow(100)){ ?>
<div onclick="getEmail();" class="listing_half_element blisting">
<div class="bcell_mid"><i class="fa fa-envelope proicon"></i><?php echo $lang['edit_email']; ?></div>
</div>
<div onclick="getPassword();" class="listing_half_element blisting">
<div class="bcell_mid"><i class="fa fa-key proicon"></i><?php echo $lang['change_password']; ?></div>
</div>
<?php } ?>