first and last scene same

If your first scene is to be repeated exactly the same at the end, do you preface the final scene with something to tell the reader we are back where we began the story or do you just rewrite it as it was?

Do you mean that it's the same scene in time? similiar to how Pulp Fiction? Then just write it out but make a note for the reader.

But if it's just a bookend scene? Just write it.

The first scene has the main character asking a question in voice over. He doesn't hear what a police officer asks him.
The final scene has no voice over, just the question being asked by the police officer.
Same place, same time, same action.
These are bookends, right?

well, it's a bookend because the movie opens and ends with it. but if you've been clear about movement in time then it shouldn't be a problem.

Think about your audience, not the reader. What clues will the audience have? Put those in the script.