If your users are unable to see their allocated printers on macOS, Windows or even Chrome OS then check any policies that you have on your account.
Within the policy creation/edit form, there is an option - 'Operating system exclusion'. If you would like printers to be available on all platforms then ensure the 'Include printer(s) on all Operating systems' option is checked.
Alternatively, if you only want printers to only appears for users on a specific Operating System then uncheck the 'Include printer(s) on all Operating systems' and check the operating system you wish to support.
