How to remove the mobile phone from the called state?

Shut down flight mode, shut down do not disturb mode.

1. When the mobile phone is in airplane mode, it will not be able to connect any signals, including phone calls and text messages. After turning off the flight mode, the phone should be able to resume normal calls.

2. Do not disturb mode is turned on, so the phone will not be connected and will be displayed during the call. Shut down do not disturb mode and release it.