Help me resolve this serious bug! When vouchur used for multiple items, their names become my cart

[icyhot]

Try it yourself!

It's very weired...

 

for example...

 

1. add "t-shirt 1" and "pants 2" in the cart

2. use the coupon code to apply discount on them

3. check them out via paypal

 

on the paypal summery, you will see they are shown as "my cart" and the quantity is 1.

However if you don't use the vochure, it's showing correctly.

I don't know what to do about it.