ddclient gives a "not yours" error even though it is my IP

I have a Ubiquiti EdgeRouter with two WAN connections. OpenDNS dynamic updates work fine on one of them. The second one always gives a "!yours" error when I try to update. I have added the network IP in the OpenDNS website and triple checked that it is correct.

Additionally, after a while (not sure how long, maybe several minutes or an hour) the network starts showing as "Inactive" on the OpenDNS website. Does anyone know what's going on?