Car seat Struggle 2015 Taurus

🖤J.🖤
I'm looking for someone who owns or uses a 2015 Ford Taurus and has properly installed an infant seat with a base inside it! My nephew has a Graco brand seat and base. The baby's other aunt, on his moms side put it in once and didn't say it was weird at all. My brother latched it in and couldn't understand why the base could slide side to side so much. Well, the latches are offset and not with the seat. The baby's mom thinks the strap you pull on the base to secure it just sucks. I didn't like Grace because of this and I feel like there's no padding in them. Anyway, I'm pregnant and trying to find out if it's my car or the base itself. I googled about the car and apparently you can install three child seats in the back...so am I just doing it wrong? I mean, all three of us must have been if that's the case because everyone first hooked it up the same way. Anyone with this car, do you have issues with your infant seats??? It's to the point we use my husbands car when we have my nephew but it pisses me off...my car is only a 2015 and quite new.