In this window settings are made for sending an SMS. To do this you need to create an account and purchase SMS credit at https://www.messagebird.nl
The API key (token) must be entered in the silence detection. Click apply and the amount of credit will be visible.
Please also enter at least one phone number.
Release of Silent detection versions 1.9.5 or lower do not require an API key but a MessageBird username and password. This does not work anymore. Upgrade silence detection to version 1.9.6 or higher for API use