Everytime I open the Confluence page with Chart Jira Gadgets, this error will pop out for at least one of them. They are always changing (first time when I open it, the fist 5/20 will have this message, second time two in the middle and 4 at the end...)
Things which sometimes help:
If that doesn't work, refresh every gadget which doesn't work for you individually:
Is there any permanent solution to this problem?
Did this happen to anyone else?