Paul said that he was a Roman citizen, so soldiers did not flog him.

Acts 22:23-29

23 While they continued shouting, “Kill him!” they took off their cloaks and threw dust into the air, which showed how angry they were. 24 So the commander commanded that Paul be taken {soldiers to take Paul} into the barracks. He told the soldiers that they should strike Paul with a whip that had pieces of bone/metal on the end of it, in order to make him tell what he had done that made the Jews shout so angrily. So the soldiers took Paul into the barracks. 25 Then they stretched his arms out and tied them so that they could whip him on his back. But Paul said to the officer who was standing nearby watching, “You(sg) should think carefully about this! You will certainly be [RHQ] acting unlawfully if you whip me, a Roman citizen whom no one has put on trial and condemned!” 26 When the officer heard that, he went to the commander and reported it to him. He said to the commander, “This man is a Roman citizen ◄Surely you would not command us to whip him!/Do you really want us to whip him?► [RHQ]” 27 The commander was surprised when he heard that. He himself went into the barracks and said to Paul, “Tell me, are you (sg) really a Roman citizen?” Paul answered, “Yes, I am.” 28 Then the commander said, “I am also a Roman citizen. I paid a lot of money to become a Roman citizen.” Paul said, “But I was born a Roman citizen, so I did not need to pay anything.” 29 The soldiers were about to whip Paul and to ask him questions about what he had done. But when they heard what Paul said, they left him immediately. The commander also became afraid, because he realized that Paul was a Roman citizen and that he had illegally commanded soldiers to tie up Paul’s hands.