Hello!
Filters need to use OData’s format, so you need to calculate when is “last day” and use its string representation. For example: $filter=TimeStamp ge 2020-08-27T02:00:20.043Z
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If you’re doing that with a workflow, you can use something like String.Format("{0}/odata/RobotLogs/?$filter=TimeStamp ge {1}", OrchestratorURL, Datetime.Now.AddDays(-1).ToString("yyyy-MM-ddTHH:mm:ssZ"))
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