Cannot read property 'toString' of undefined

I installed and configured grafana with combination of elasticsearch and logstash,
my issue is I am trying to create pie-chart but it showing like this Cannot read property ‘toString’ of undefined pls any one help me .

hi daniellee…
I’m trying to create dashboards it showing error like this Cannot read property ‘toString’ of undefined please any one help me .

You need to provide more information for me to be able to help you. Can you take a screenshot?

Pie chart panel only supports time series. so you need date historgram. Specify a large time interval (1y for example) to get only 1 data point.

You data source name looks strange. You know you can specify data source index patterns for daily elasticsearch indices. Grafana will generate the daily index names depending on time range.