Answer: The network time feature is also called NITZ. Before using this feature, please make sure your network provider supports this feature.
To enable this feature you have to set <AT+CTZU=1>. Then whenever you need the network time, you can get it by <AT+CCLK?>.
You can also use command <AT*PSUTTZ>, but it is less common. If you set <AT*PSUTTZ=1> then there will be the URC of "*PSUTTZ ...” after module startup which contains the network time.
AT+CTZU=1 ==> Enable automatic time zone update via NITZ
+CCLK: "12/01/06,07:51:26+04" ==>Time is updated
Please you can also refer to 3GPP TS 27.007, 8.39 Automatic Time Zone Update +CTZU for further information.