You can choose to ignore the contact, or add them to CRM.  If you ignore, you can always remove them from the ignored list later.

If you would like to bulk Ignore contacts on the list, select the checkboxes next to the emails you want to bulk Ignore, then click "Actions" "Ignore All Selected".

Enter the contact details and search for a CRM account or agency to attach it to. \
\
**Be sure to attach Agency contacts to the correct Agency, not an account under the Agency. Agency contacts should be associated with the Agency, not the account.**\
\
Once done, the system will remember that choice and the contact will not show back up in Unknown.