Wheel/Driveshaft Issue?

Hey guys, so for awhile now I’ve noticed the front left tire on my ’14 Polaris Sportsman 400 slowly moving inwards towards the metal piece that connects the tire to the wheeler (is it called a hubstrut?). I took the hubcap off and tightened the bolt after removing the cotter pin, but it still is rubbing. If we jack the wheeler up and move the tire around, it wobbles. A friend of mine told me that it may be due to something that connects the driveshaft to the tire, and I have no idea what that part may be. If anyone has had any issues like this, could you help me out? I realize I may have to take it to a mechanic, but I would like to assess perhaps how much it will cost. Any help is appreciated. Thank you!