Description of problem:
On editing zones sometimes this error is generated when trying to save runtime config to permanent after adding a service. It appears mostly consistent on these steps but I've saved runtime on public before in the past and this is failing now. It's worth trying dmz or work or similar if on trying to reproduce public works.

Version-Release number of selected component (if applicable):
firewalld-0.3.9-11.el7.noarch

How reproducible:
Always on certain zones

Steps to Reproduce:
1. firewall-cmd --set-default-zone=public
2. firewall-cmd --list-all
public (default, active)
  interfaces: eth0
  sources: 
  services: dhcpv6-client ssh
  ports: 
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules: 
3.firewall-cmd --add-service=ntp
4. firewall-cmd --list-all
public (default, active)
  interfaces: eth0
  sources: 
  services: dhcpv6-client ntp ssh
  ports: 
  masquerade: no
  forward-ports: 
  icmp-blocks: 
  rich rules: 
4. firewall-cmd --runtime-to-permanent
Error: RT_TO_PERM_FAILED: zone 'public' : ZONE_CONFLICT


Actual results:
Error: RT_TO_PERM_FAILED: zone 'public' : ZONE_CONFLICT


Expected results:
'success' being shown and the current firewalld runtime being committed to disk

Additional info:
using firewall-cmd --add-service=ntp --permanent correctly writes the changes to disk but defeats the point of the runtime-to-permanent capability to safely make certain changes (perhaps with an "echo firewalld-cmd --reload | at 15 mins" for safety) and then commit them to disk.