How can I know the phone number of the destinatary?

[fercom]

I want to connect multiple phone numbers to the same webhook, is it possible to know the destinatary of the users message?
I know that the users number is it here:
textMessageReplyRequest.To = textMessage.SingleOrDefault().From;

But I want to know the "to" field for giving different info to the user depending of what number is it contacting

[fercom]

I found it, it is in:

var displayPhoneNumber = Convert.ToString(messageReceived["entry"][0]["changes"][0]["value"]["metadata"]["display_phone_number"]);