All inbound and outbound messages to and from new phone numbers will create new entries in your Address Book. To reach your Address Book, click Address Book > Contacts at the top of your home dashboard.
From here, you can search for existing contacts in the search bar, filter to see unsubscribed contacts, bulk update contacts, and use the View button to update Contact Details for specific people. You can include a Name, Email, Photo, Tags, and other Notes in the Contact Details. If you're on Textline's Standard plan or above, you also have the option to create your own Custom Fields for your contacts, so you can include whatever information is relevant for your company.
You can add individual contacts manually to your Address Book by clicking the blue New Contact button, or perform a mass import of an existing contact database using a CSV file, for which you can download the template here.
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