Depending on your plan level your account may include Contacts.

Contacts contain all of the phone numbers that have been added to your account in one combined view. This includes any phone numbers that have texted a keyword or have been uploaded from an external source such as a .CSV file.
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You can find your contacts table by selecting Contacts from the navigation.

From here you can see all of your contacts as well as import new contacts from a .CSV file. When you first open the contacts able you will see all of your contacts including those who have Opted-Out. You can filter your contacts by either All Contacts, Active, or Opted-Out by selecting the filter at the top of the table.
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