Hello, Can I speak to Tom, please?
I'm afraid he is not in at the moment.
May I ask what time he will come back?
I think he will come back at 3 p. m. Do you want to call later? Or would you like to leave a message for him?
I'd like to leave a message. Please ask him to call me back as soon as he returns. I'm A and he has my number.
OK. I will do that.
Thank you very much. Bye.
You're welcome. Bye.