Agreed that poor shifting is Boy right on a new bike. But do understand that internal routed shift cabling will have greater friction and maintenance needs then classic and straighter outside routing. To a degree this is some of the "cost' of the decision you made when you bought the bike.

Having said that you should take the bike back to the store you bought it from and have them go through the shifting system to make sure that there are no other issues adding their aspect. Like the exposed casings are cut clean, well capped and with nice smooth loops. Like the inner cables have no kinks or distorted sections in them. We add TriFlow to our inner cables as they pass through and around the casings and guides.

Good luck. Andy.