To use the replay feature, tap the replay button (circle with back arrow) on the left end of the player controls.
Ad-supported listenerswill be prompted to watch a video ad to receive replays. You can then play back any song in your session history that has an active replay icon (until your replays are used up).
For Pandora Plus or Pandora Premium listeners, replays are included with your subscription. You can play back any songs with an active replay icon whenever you like.
Keep in mind that you may encounter some songs that aren't replay-eligible. When this happens, you should see a message letting you know the reason why, although this limitation is typically a result of a content licensing restriction.