How to remove a subinterface

Do you have anything bound to that sub-interfaces ( vpn,dhcp-server, fwpolicies, vips,etc...) if it has any objects attached via some configurations, then you would not beable to delete it. What you could do; rename the sub-interface and edit out the vlan-id to the correct vlan-id #. If you really need to delete it, upgrade to the new code which gives you a dependencies check/attach buttom or down load the config to a text editor and Find ( grep ) on the interface name.

OK, I have only fw policies. Which CLI command for rename subinterface and modify vlan ID ? I have tried in config system but it' s not good. please

 config system interface      edit " vlan12"           set vdom " root"           set interface " internal"           set vlanid 12      next      edit " vlan32"           set vdom " root"           set interface " internal"           set vlanid 32      next  end    gate (interface) # ed vlan32  gate (vlan32) # set vlanid 33  next  VLAN ID or physical interface cannot be changed once a VLAN has been created.  object set operator error, -522 discard the setting  

And there' s no ' rename' command in ' config system interface' . But a ' delete' ...

Finally, I deleted the subinterface by removing all objects attached. Thank you for help