THE DECISION
The referee drops the ball again for Team A player.
Read official Law 8 ↗Explanation
A dropped ball is in play when it touches the ground. However, Law 8 has a specific instruction for what happens next: if it leaves the field of play without touching any player, the referee drops it again.
That is why Team B does not receive a throw-in here. The ball reached the touchline after touching the ground, but no player touched it. The original drop is repeated for a Team A player.
If a player had touched the ball after the drop and it then crossed the touchline, the normal throw-in decision would apply according to which team touched it last.