Помогите составить диалог между двумя друзьями на тему "On the telephone"

Good morning. Robert Smith speaking. 
Good morning. This is Artyom Mironov. I would like to speak to Mr. Brown. 
Oh, sorry. Mr. Brown is not here, yet. 
Can you tell me when he will be in? 
Probably around 4 pm. Alright, I will call again later then.
Thank you. 
You’re welcome.
 Bye. 
Bye.