Steering wheel shakes while driving

These last few weeks, I have had issues with my steering wheel shaking while driving over forty mph. Went to a shop and they told me my tires were bad, so I purchased new tires and had an alignment done which did not fix the problem I was having.

I took my vehicle to another location to have them look into this further and I was told my wheels on the front were bent which the tire company did not tell me about.
So they moved the bent wheels to the rear until the new ones came in. A few days later I went back to have the new wheels put on and while driving home it was doing the same thing as before.

I went back to the tire company and explained to them what problems I was having. They told me the tires were not balanced and aligned correctly, so they balanced them again. I took my car in today to the place where I had the alignment done and it explained to them what the tire company told me. The mechanic looked into this further and agreed the alignment was not done correctly, so they did it again and told me that it was driving better now.

I started driving home, and the steering wheel is still shaking. Not sure what is causing this to happen. Does anyone have any idea what could be the problem?