Phone Settings; Save Changes - DBL Technology HT-912T User Manual

3.3.4. Phone Settings

A) PhoneBook Function: Configure *50, you can use PhoneBook, if you need to dial
first number on PhoneBook, press *501#.
B) FXS 48v Standby: Use when standby.
C) Billing Support: Enable the call hold, with the HOLD key to use.

3.3.5. Save Changes

When you finish settings, click "save change" save all the settings.