Is the appropriate printer driver installed?
This should help to setup your printer via CUPS. If your printer has a PPD in the CUPS database, it should work for you.
- CUPS ArchWiki
There is also a Brother HL-2030 CUPS driver available via the AUR, which may (or may not) be a valid alternative.
Note that the AUR is not supported by Manjaro (or Arch). Any software installed from that source is used entirely at your own risk.
pamac build brother-hl2030
Otherwise
Cheers.