There are three ways by which a ticket leads to the Spam folder -

  • Manually marked as Spam by an Agent. 
  • Ticket marked as Spam by an Automation rule such as the Dispatch'r or the Observer. 
  • Any ticket raised by a "deleted contact" in Freshdesk would go to Spam automatically.

To have this resolved, kindly ensure that there are no automation rules that would mark tickets as Spam automatically and also make sure that the contact is restored from the Deleted list under the Customers tab.