When it is not good time to talk to the other person on the phone, you should know how to stop the conversation politely.
1）I am sorry, but I'm unavailable now.
2）I am sorry, but I am in a meeting right now.
3）I'm sorry, but I in the middle of something.
4）I'm sorry, but I'm new to the company.
A: I am calling about our new product line. What's the status of it ?
B: I'm sorry, but I'm new to the company. I'll connect you with someone else.
A: OK. Go ahead