It appears like that because they are in fact there, and they are not doubled, one of the annotations is k8s.v1.cni.cncf.io/network-status and the other one k8s.v1.cni.cncf.io/networks-status. These seem to be added by multus, moving to sdn team.
As Standa mentioned, this is not duplicated, 'k8s.v1.cni.cncf.io/networks-status' and 'k8s.v1.cni.cncf.io/network-status', networks v.s. network. Let me introduce the history. Previously multus-cni uses "k8s.v1.cni.cncf.io/networks-status" for network status as original implementation. Then Kubernetes Networking Plumbing working group creates the de-facto standard, multi-net-spec. https://github.com/k8snetworkplumbingwg/multi-net-spec/tree/master/v1.1 In this spec, "k8s.v1.cni.cncf.io/network-status" is used, then we, multus team in upstream, decides to change it. Currently we're in transitional phase, hence we need to keep old one and new one for compatibility. That is why we have two status. We are going to remove old one after a few releases. So if you don't mind it, I am going to change this bz to 'closed'. Please let me know if you have question/comments.
I agree with Tomofumi's comment 2, thanks
Since the problem described in this bug report should be resolved in a recent advisory, it has been closed with a resolution of ERRATA. For information on the advisory, and where to find the updated files, follow the link below. If the solution does not work for you, open a new bug report. https://access.redhat.com/errata/RHBA-2020:2409