[cflsystems]

Try this

{if $active_modules.Extra_Fields ne ""}
 {include file="modules/Extra_Fields/product.tpl"}
 {section name=field loop=$extra_fields}
  {if $extra_fields[field].field_value and $extra_fields[field].service_name eq "SERVICE_NAME15"}
   {assign name="url" value=$extra_fields[field].field_value}
  {/if}
  {if $extra_fields[field].field_value and $extra_fields[field].service_name eq "SERVICE_NAME13"}
   {assign name="anchor" value=$extra_fields[field].field_value}
  {/if}
 {/section}
 {if $url and $anchor}
  <tr>
   <td colspan="2" align="center" class="PlantBoxFooter">
    <a href="{$url}">{$anchor}</a>
   </td>
  </tr>      
 {/if}
{/if}