Sagem COSY Phone Manual page 23

- Select Activation and enter password.
Blacklist
The blacklist is used to limit failures on automatic calls (calls
generated by the automatic redial function or by
applications: data, fax for example).
When several automatic calls failed with a number (number
busy or unknown), this number is put in the blacklist and no
automatic call will be done with this number any more until
you delete it from the backlist.
NOTE: this function does not apply to the calls performed
manually.
Calls 23