Gateway:
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API Key : Get the API Key and set it
Callback URL : The callback url is set by the installation of the plugin. It deals with receiving updates from the SMS.to site for the sms sent. i.e A callback sent from SMS to site will change the status of a message from ONGOING to SENT. If the Callback URL is not set, then no callbacks will be sent. If you need to change this, please do it with caution
Sender : Sender for all SMS sent. The Sender field is set by the installation of the plugin to SMSto. You can change this to any value. The maximum length of the sender is up to 11 characters.
Gateway Status : Shows information regarding the status of the gateway. Whether is active and supports Bulk SMS. It also shows the remaining balance
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