Getting error while creating grafana report from opennms


I have created some dashboard in grafana. Grafana report can be generated from database report in opennms. I have configured grafana endpoint in opennms according open nms document. After generating grafana report, a pdf file has been created. But pdf file open with blank pages with error message and nothing found on internet about the issue. How can I solve this issue.

Thanks in Advance

Verify your Grafana URL is correct.

Thanks @dino2gnt for replying

Actually I am using url. http://hostname:3000/ in grafana endpoint. Test connection is showing connected.