There is an icon I cannot get rid of! It's aggravating! Cannot move it off my display screen! It's round, and when pressed, opens up to like a mini settings! If I can't get it off, I'm liable to get another phone, with possibly another carrier!
Could you possibly have the "Assistant menu" enabled? It shows up as a circle with 4 squares inside.
To disable "Assistant menu", go to Settings -> Accessibility -> Interaction and dexterity and turn it off.