Configuring Agent Subscription
Telephony Service > Subscribers > Subscriptions > Characteristics (1.2.3)
Set the following fields:
Call waiting | REFUSED |

Note:
Under Keys, only set a single number as Monitoring your number (COO).
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Telephony Service > Subscribers > Subscriptions > Characteristics (1.2.3)
Set the following fields:
Call waiting | REFUSED |
Under Keys, only set a single number as Monitoring your number (COO).