Trying to reach a co-worker on the phone

— Do you know where Tanya is? I've been phoning her and sending e-mails for the past hour. She's not at her desk.
— She had to go to the downtown office to clear up a problem. Apparently, they sent us the wrong invoices.
— Well, I have some good news. We have a new advertising client, and I want Tanya to be in charge of their account.
— That's great news! You should call her on her cell phone. I'm sure she'd rather hear the news from you than read it in an e-mail.