How do you disable NAT on UTM 9?

I have research sops support posts and the net, but there does not seem to be clear instruction to disable NAT with UTM 9.

I have servers with public IP's behind the UTM as their gateway and the network traffic looks to be impaired by NAT running on the router.

I do not have any NAT rules in place.

Any help would be appreciated.

Thanks,

Patrick