[fix] catch-all receiving emails to alias NOT marked "active"

## Describe the bug

**Description:** I have a paid account with a catch-all alias which is marked "active" for my domain (call it `example.com`). I then have another normal alias (call it `inactive@example.com`) which is NOT marked "active" with the expected response set to "550".

## Actual behavior

The catch-all receives emails sent to `inactive@example.com`.

## Expected behavior

Emails sent to `inactive@example.com` receive the 550 error code.

## Checklist

- [x] I have searched through GitHub issues for similar issues.
- [x] I have completely read through the README and documentation.
- [ ] I have tested my code with the latest version of Node.js and this package and confirmed it is still not working.