I found out today that service requests with pending approvals can still be closed, and the action cancels the pending approval request.
In our case, we need two people to approve some service requests. What happened was that the service requests with one approval done and one pending approval request had its Status changed to "Closed". This cancelled the pending approval request and automatically changed the Approval Status to "Approved".
I saw another user had reported this problem and a freshplug was provided. It would have been better if that freshplug was accessible and not privately shared to that users, so those of us who also want to put a validation for approvals could add it to our system. (See https://support.freshservice.com/support/discussions/topics/313760).
It would be great if you could add this feature soon!