HI,
I would deeply aprechiate if someone here could help me address a problem with ACL. I would personally refrain from e-mailing ever so often as I understand other users have more important issues to discuss about. Anyways I hope someone here could help.

When I run ;-
 doveadm acl get -A Public/Archive
I keep getting an error that says Mailbox does not exist . See erorr message below : -

Error: Can't open mailbox Public/Archive: Mailbox doesn't exist: Public/Archive

In the fastmail folder there is a folder called Archive, why isn't it being read?  The folder is drwxr-xr-x. with vmail as owner.

Deeply appreciate if someone could help with this.
Many  thanks

dovecot -n output :-

# 2.3.3 (dcead646b): /etc/dovecot/dovecot.conf
# OS: Linux 4.20.10-200.fc29.x86_64 x86_64 Fedora release 29 (Twenty Nine)
# Hostname: machine
auth_mechanisms = plain login
mail_location = maildir:~/Maildir
mail_plugins = acl
mail_privileged_group = mail
mbox_write_locks = fcntl
namespace {
  list = children
  location = maildir:/run/media/computer/Storage/Email/fastmail/
  prefix = Public/
  separator = /
  subscriptions = yes
  type = public
}
namespace inbox {
  inbox = yes
  list = yes
  location =
  mailbox Drafts {
    special_use = \Drafts
  }
  mailbox Junk {
    special_use = \Junk
  }
  mailbox Sent {
    special_use = \Sent
  }
  mailbox "Sent Messages" {
    special_use = \Sent
  }
  mailbox Trash {
    special_use = \Trash
  }
  prefix = INBOX/
  separator = /
}
passdb {
  driver = pam
}
passdb {
  args = /etc/dovecot/dovecot-sql.conf.ext
  driver = sql
}
plugin {
  acl = vfile
}
postmaster_address = postmaster at example.com
protocols = imap pop3
service auth-worker {
  user = vmail
}
service auth {
  unix_listener /var/spool/postfix/private/auth {
    group = postfix
    mode = 0666
    user = postfix
  }
  unix_listener auth-userdb {
    mode = 0600
    user = vmail
  }
  user = dovecot
}
service imap-login {
  inet_listener imap {
    port = 143
  }
  inet_listener imaps {
    port = 993
    ssl = yes
  }
}
service lmtp {
  unix_listener /var/spool/postfix/private/dovecot-lmtp {
    group = postfix
    mode = 0600
    user = postfix
  }
}
service pop3-login {
  inet_listener pop3 {
    port = 0
  }
  inet_listener pop3s {
    port = 995
    ssl = yes
  }
}
ssl = required
ssl_cert = </etc/pki/dovecot/certs/dovecot.pem
ssl_cipher_list = PROFILE=SYSTEM
ssl_key = # hidden, use -P to show it
userdb {
  driver = passwd
}
userdb {
  args = uid=vmail gid=vmail home=/var/mail/vhosts/%d/%n
  driver = static
}
protocol imap {
  mail_plugins = acl imap_acl
}