Need help in Provisioning the Load balancer for Istio-ingress gateway in RKE cluster

Currently, I’m using 3 EC2 instance for running a RKE cluster and Metallb for provisioning the load balancer,
In config file for Metallb, I wrote the private ip address of EC2 instance in range format.
Now, it has allocated the same for the external ip of the Istio- Ingress gateway service.
After deploying an application using Istio, it’s allocating the private ip address as part of Gateway for the URL.
It is not accessible from the outside world. Only, the nodes, which are connected for forming cluster is able to curl the private ip URL. Example:
Kindly please provide a working solution.