Illegal participation ?
 

3rd and 10 at Team A’s 35 yard line. A1 is running a pass route down the sideline. A the legal pass reaches his position, A1 tips the ball.steps out of bounds and then comes back in bounds at the 50 yard line,A1completes the catch as he falls to the ground at Team B’s 46 yard line.

IP.

A and K cannot go out of bounds accidentally and come back in. This is a foul unless he was somehow pushed out.

Peace