In order to enable SMS and MMS services you have to configure these services at your service provider and in Configuration Manager.
SMS Gateways section allows you to configure SMS Gateways, your connections with SMS providers, that allow you to send and receive SMS messages.
Create/Edit SMS Gateway
Name. Unique alphanumeric name for the SMS Gateway (no spaces or special characters are allowed).
Provider. Name of the SMS service provider. Currently Telnyx, Twilio, and Bandwidth are supported.
Description. Description of the SMS Gateway, optional.
Domain. Domain to be used to receive inbound SMS messages and status information sent by your SMS provider
The rest of the parameters may be different, and depends on the SMS provider you selected.
API Key. Provided by Telnyx.
Account SID. Provided by Twilio.
Auth Token. Provided by Twilio.
Application ID. Provided by Bandwidth.
Account ID. Provided by Bandwidth.
Auth Token. Provided by Bandwidth.
API Secret. Provided by Bandwidth.
Set URL at a service provider
Once the SMS Gateway is created, Configuration Manager will generate a URL for receiving inbound SMS messages and status information sent by your SMS provider. You need to specify these URLs at your SMS provider's portal.