Yealink SIP-T23P User Manual page 99

2. In the DND block, mark the desired radio box in the Mode field.
3. Click Confirm to accept the change.
Note
DND mode is configurable via web user interface only.
To activate DND in phone mode:
1. Press the DND soft key when the phone is idle.
The icon on the status bar indicates that DND is enabled.
Basic Call Features
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