Istio Dashboard failure on Resizing Kubernetes cluster

I have recently installed Istio 1.7.3 in Kubernetes Cluster (GKE) on Google Cloud and various other addons like Grafana Prometheus dashboards, etc.
I have configured the dashbaords with Istio Service and other parameters, they started working when I resized the cluster size to 0(zero) and again after few time resize it to 2(or as per requirement). I found that the configured dashboard are not available after the resizing process of cluster. All the dashboards are not available also the users I have created also not there.
What is the good practice to install and manage ISTIO with other dashboards?