.png.022b5452a8f28f552bc9430097a16da2.png)
The printscreen is from official demo from Prestashop site:
https://demo.prestashop.com/#/en/back
Reference on combinations are ok. Below is another prontscreen from combination. In orders ---> shoping carts should be "Demo 16" reference, but there is second product name.
In my shop in presta 1.7.7.0 is the same bug 
.png.c13492010b66318fa8dda6e61117a15d.png)