You make, for example. group e-mail “support” and all e-mails with this label go to it and users can create tickets from this group e-mail. You can then turn each email into a ticket.
In principle, this is a function very similar to tasks, but there is a visible e-mail communication with the contracting authority, which is kept in the system, and this is also in order not to mix external requirements with internal tasks and projects.