Basket page is trying to combine products when it shouldn't be doing it on kit component choices.

Steps to reproduce with sample data:

Edit the Build A New Pet Care Package product in admin
Go to Kits tab
In the first component (Dogs), add existing product
Select Feathered Cat Pole and add it to the kit component

Save the product. Now you have the same product available as a choice in two different kit components.

Preview the product.

For the Dogs component, select Feathered Cat Pole.
For the Cats component, select Feathered Cat Pole.
Remaining component choices do not matter. Add the product to the basket.

Basket page will render and initially show Feathered Cat Pole twice. Once for Dogs, again for Cats.

Refresh the basket page. Now it only shows once.

Keep refreshing the page and you'll see it flip back and forth between showing Feathered Cat Pole once and then twice.

The basket Combine() routine is not behaving consistently, and not behaving properly with kit component choices that have the exact same name.

I appreciate the offer. We've got a fix in place that resolves it, no need to distract the team on our behalf.

The root issue is traced down deep into the code that wants to combine like products into a single basket item. It's combining based on product name only, which is fine for everything. Except kit components that generate multiple line items with identical names. We modified the basket page to simply render the quantity with the component name if it's greater than 1. So either way, the display is accurate to the shopper for that one page.

We also confirmed as you did the remaining checkout pages render accurately at all times.