Network must be converted to a managed error while adding new dhcp network

[#1]

Hi All,

We are adding a new dhcp network under data management -> dhcp but on the wizard step 3 we are getting this error Network (our new network) must be converted to a managed.

Did we missed anything before this or ??

[#2]

Most likely, there is an unmanaged network already present.  If so, that network should be converted to managed, instead of being created as new.

[#3]

how to converted to manage? if unmanaged scope is presented