Message "SyntaxError:Unexpected token '<', "<!DOCTYPE"...is not valid JSON" shown when use Dashboard

[Lê Thùy Linh]

My client cannot view dashboard (using rich filter) I created because when he accessed, the error message has been shown (error message appreared inside the gadget of each dashboard)

"SyntaxError: Unexpected token '<', "<!DOCTYPE"... is not valid JSON"

I add him to project with role "Customer". I try to add my team with role "Customer" as well but she still see the dashboard as normal so I think it's not the problem with permission

Please tell me what's the problem here

Thank for your support

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