Approval Processes invoked by an action rule do not send an email to the technical team or client when the ticket is approved or not approved.
When an action rule is created, it should add an approval process based on some criteria. This approval process is not linked to the ticket request type. After the ticket is approved, Web Help Desk does not send an email to the tech or client.
This is a bug in the Web Help Desk versions mentioned above.
This issue was resolved in Web Help Desk 12.4.