Gigaset PREMIUM 300 Manual page 45

Setting the protection mode
Settings
Protection Mode
No Protection
Silent Call
Block Call
Save settings:
OK Telephony
OK select desired protection:
All calls are indicated, including from callers whose numbers are on
the black list.
The telephone will not ring and the incoming call will only appear in
the display.
The telephone will not ring and the incoming call will not appear in
the display. The caller will hear the busy tone.
Save
Protection against unwanted calls
OK Black List Edit
45