Yealink SIP-T23P User Manual page 87

A numbered prompt appears on the LCD screen, for example "2/3", indicating that this
is the second call out of three calls.
If multiple calls are placed on hold on more than one line key, you can view call details
by pressing the corresponding line key, and then press the Resume soft key to retrieve
the call.
You can use DND to reject incoming calls automatically on the phone. The prompt
message "n New Missed Call(s)" ("n" indicates the number of missed calls) will appear
on the LCD screen, and callers will receive a busy message. All calls you receive while
DND is enabled are logged to your missed calls list.
Note
The prompt message will display only if Missed Call Log for the line is enabled. Missed
Call Log is configurable via web user interface at the path Account->Basic.
Do Not Disturb is local to the phone, and may be overridden by the server settings. For
more information, contact your system administrator.
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.
Basic Call Features
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