What if you really don't want to answer a person's phone call, but you can't refuse it directly?

Turning a mobile phone into a busy line is call forwarding, and you hang up when he calls. The transfer number is down or empty, and you will say the same if you hang up. Follow-up: How? A: In the call settings, there is a call setting. When busy, click Transfer, and then click Open to enter the stop number or empty number. Press ok. So you can pick up whoever you want. Will not be asked by most people: if that person calls again after setting up, he will say that it has stopped or the number is empty. Is it possible for me to refuse?