The Twillio/WhatsApp integration collects both SMS and WhatsApp messages sent to a Twillio number. The current issue is that if you have received an SMS message, you are unable to reply to the sender as Front attemps to send this as a WhatsApp message which has two issues:
There is no gaurantee that the sender has WhatsApp
In the eyes of WhatsApp, this is a cold message as we aren't responding to a WhatsApp message.
It would be beneficial if we could use the same number for SMS and WhatsApp to allow our customers to contact us via any messaging service. We want to avoid having to have a separate number for SMS and WhatsApp as this could get confusing for the customers.