What happens if you follow this “hack” procedure?
EDIT: a useful tip: just for an easy visual access of the entire table of clients, you can have all your network IPs, including the hosts fixed IP, in the “Current Fixed leases” of the DHCP page of the WUI, just do not activate the “enabled” checkbox for the hosts entries. This can be a way to have everything documented in one place. Unfortunately I do not remember to whom should I give credit to for this tip. I think it was @bonnietwin but I am not 100% sure.