[RHOCP 4] Failing to create a Network Attachment Definitions (NAD) with Dual-Stack networking inside pod

Issue

• Problem getting an IPv6 address assigned to a Network Attachment Definitions (NAD) when additionalNetwork is created with dual-stack networking.

• Getting the below error in the natgateway pods:

  Events:
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    Warning  FailedCreatePodSandBox  27s   kubelet            Failed to create pod sandbox: rpc error: code = Unknown desc = failed to create pod network sandbox k8s_natgateway-xxx(...): error adding pod default_natgateway-xxx to CNI network "multus-cni-network": plugin type="multus" name="multus-cni-network" failed (add): [default/natgateway-xxx/xxxxx:yyyyy]: error adding container to network "yyyyy": invalid CIDR : invalid CIDR address:
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