Yealink SIP-T54S Administrator's Manual page 285

Enter the time and date in the corresponding fields.
3.
Click Confirm to accept the change.
4.
To configure the time and date formats via web user interface:
Click on Settings->Time & Date.
1.
Select the desired value from the pull-down list of Time Format.
2.
Select the desired value from the pull-down list of Date Format.
Click Confirm to accept the change.
3.
To configure the time and date manually via phone user interface:
Press Menu->Basic->Time & Date->General->Manual Settings.
1.
Enter the date and time in the Date Time field.
2.
Press the Save soft key to accept the change.
3.
To configure the time and date formats via phone user interface:
Press Menu->Basic->Time & Date->Time & Date Format.
1.
Press or , or the Switch soft key to select the desired time format from the Time
2.
Configuring Basic Features
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