我该如何处理：

object network obj-nat_DNS1
 host 10.128.33.11
object network obj-nat_DNS2
 host 10.128.33.12

并将主机更改为不同的 IP？我不是要删除网络对象，只是修改它们。我试过这个：

object network obj-nat_DNS1
 no host 10.128.33.11
 host 10.128.33.21
object network obj-nat_DNS2
 no host 10.128.33.12
 host 10.129.22.22

我得到了：

ERROR: unable to delete object (obj-nat_DNS1). object is being used.