Zero dollar coupon show on invoice

I'm using a coupon code with a value of 0.001. This shows as 0.00 in the cart, which is what the client wants. However it does not show in the invoices. I need it to show in the invoice. How can I do this?

I have enabled "zero value coupon" in Joomla > Components > AwoCoupon > AwoCoupon > Configuration > General > Enable zero value coupon.

The zero dollar coupon still does not display on the invoices.

joomla 3.5.
AwoCoupon Pro 2.4.9
Rupostel OPC 2.0.312

Hello,

AwoCoupon does accept the coupon, and you can see it in the order. The invoice must be looking at the value of the discount, and if it finds it to be 0, not add the coupon. So have to look at the invoice code to get this to work.

Thanks Seyi

FYI,

component > com_virtuemart > views > invoice > tmpl > invoice_items.php
line 170
if ($this->orderDetails['details']['BT']->coupon_discount <> 0.00) {

and

component > com_virtuemart > views > orders > tmpl > details_items.php
line 112:
if ($this->orderdetails['details']['BT']->coupon_discount <> 0.00) {

removed <> 0.00 and it printed in the invoices.