Yealink SIP-T42G - Manual (Page 87)

Basic Call Features
77
Multiple Calls on Hold:
If multiple calls are placed on hold, do one of the following:
- Press or to switch between the calls, and then press the Resume soft key
to retrieve the desired call.
- Press the corresponding line key to retrieve the call.
If more than one call is placed on hold, a numbered prompt appears on the LCD screen,
for example "2/3", indicating that this is the second call out of three calls.
You can use DND to reject incoming calls automatically on the phone. Callers will
receive a busy message.
You can enable/disable DND for the phone system, or you can customize DND for each
or all accounts. Two DND modes:

Phone (default): DND is effective for the phone system.

Custom: DND can be configured for each or all accounts
You can receive incoming calls from authorized numbers when DND is enabled.
To configure the DND mode via web user interface:
1. Click on Features->Forward & DND.
2. In the DND block, mark the desired radio box in the Mode field.