Define a Virtual IP (Alias) to act as a load balancer

Question

I need to define a Virtual IP (Alias) to act as a load balancer for three hosts, utilizing a round-robin policy. 
 I assigned the Virtual IP alias to the physical interface corresponding to the LAN port of the Sophos XG. On the same interface, I also configured several VLANs. Following this, I created a NAT rule as shown in the image below: 
 
 The Virtual IP (10.10.30.50) is not accessible from the same subnet (10.10.30.0/24); however, it functions perfectly when accessed from other subnets. 
 Could you please advise on how to resolve this issue? 
 Thank you in advance for your help!

Angelone · Answer

I resolved the issue by creating a new firewall rule that allows traffic from the DMZ zone (any host) to the DMZ zone, with the alias IP as the destination: 
 
 Now the alias IP is reachable both from the same network and from other subnets. This seems weird! Why is an explicit rule necessary to allow traffic within the same zone?