After applying SSL Templating init failed issue

I have installed Grafana in Centos 7, I am using Prometheus as the data source.
While accessing the grafana in HTTP it’s working fine, all the metrics collected by Prometheus is showing in grafana dashboard.
My issue is, after applying the SSL to Grafana, the dashboard is working fine, but the Prometheus metrics of kubernetes is not displaying in Grafana dashboard, it’s showing me Templating init failed error.
And also I inspected the Grafana dashboard in google chrome, in the console it’s showing me Mixed content error.
Here I attached the screenshot of the Grafana dashboard.

Can you help on this…!