NAT IP Alive - IP not Assigned as a alias

Hello everyone, 

I have some doubts about configuring DNAT rules on a Sophos XG. Currently we're on a migration firewall process checkpoint to sophos. According with the information all the public IP pool is configured on a checkpoint firewall to publish services of our client, but yesterday we start to configure DNAT rules to migrate the same rules of checkpoint, the case is when we do this, all the published services of checkpoint started to down. 


Here is the doubt, Why did these services start to fail, since the public IPs were not configured in the interface as aliases on sophos?. All the Public IP was configured as a host object on the firewall but are not alive and the rules are all disabled.


Waiting for your early reply. 


Best Regards!