Oops we hit a snag/upgrade online

I've had this problem since last year. I have never successfully upgraded online. I am convinced that they are doing it on purpose so that we have to go in the store and decline their additional sales and add ons. I've been fighting with cust support online about his issue all week, and they keep jumping "So do you wanna just buy that with me" and I am like NO …. I want to address the issue.