Planet Technology VIP-320 - Manual (Page 46)

6. Press button to show option code
7. Press button to select [BARRING]
The base can setting barring number, if the first-part digits of dial
number are the same as barring number, then the dialing number will
be block.
Press to switch from [No1:] to [No4:] and button for enter, C
for cancel, then select handset to active barring number.
This setting is using for barring number.
3232242432
BARRING
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