Car shakes when getting on high way

I got after market rims professionally installed and everything was fine for a few days when I notice driving on the high way the car would vibrate and shake mostly in steering wheel but felt it throughout whole car. I brought it back to the tire shop where it was installed and they rebalanced them and said I needed hub rings which they put on while I was there. Now it's been about a month and car is shaking while accelerating onto highways again. The shaking is mostly in steering wheel again and occasionally the whole car will go slightly to left or right. Is it possible for the hub rings or weights to fall off? How would I check it if they did? And how do I make sure this doesn't happen again?