Grafana Getting Internal Server Errors Communicating with Graphite

When accessing a dashboard called leaderboard, I am getting the following log error:

t=2019-06-24T15:57:09+0000 lvl=eror msg=“Request Completed” logger=context userId=1 orgId=1 uname=siteoptz method=POST path=/api/datasources/proxy/3/render status=500 remote_addr=172.17.0.1 time_ms=36 size=653 referer=“http://grafana.staged-by-discourse.com/d/000000060/leaderboard?orgId=1”,

For some reason I am getting an Internal Server error (HTTP 500).

Any help on how to fix would be much appreciated.