Thanks for your quick reply. When the exchange calender event is upcoming, the "flow" will send a reminder email to a group member to upload document to a sharepoint document library .If he will not upload document after 5 days, the "flow" will send an reminder email to him again. I think you asked a good question, I don't know what criteria can be used to determine if a document associated with an event has been uploaded? There is no link between the document and the event. So I can not design this flow ,the criteria is based on whether or not the document was created . Please help me find a way to desgin this flow. Thank you very much.