what is the inconsistency in the booking process? You booked a canade basic exonomy fare, which is eligible for a carry on and the display gave a green check for it when describing the restrictions. Your ticket is properly endorsed for a canada basic economy fare, which means you have the proper fare basis.

As long as you haven‘t created a fare break in the US, there should be no issue. If you want people to validate fuerher, go under my trips and view the fare rules. You can post just the fare basis and people would be able to advise you.

edit: you certainly have a fare break if you‘re getting N on one of the segments. But I‘m curious what day or how you‘re searching - your original screenshot is showing only the 2 stop options when there are multiple 1 stops available. Even when I dig to find those 2 stops it‘s not creating fare breaks.