Hi Abhishek,

Yes, it's possible to automatically update the stage of an opportunity to "Closed" when the Stop Sale date is reached using a flow in Salesforce. Here are the high-level steps to achieve this:
- Create a new Flow in Salesforce.
- Add a new variable of type Date, let's call it "Today's Date".
- Add a "Get Records" element to retrieve the Opportunity record with the Stop Sale date field.
- Add a "Decision" element to check if the Stop Sale date has passed. You can use a formula to compare the Stop Sale date with the "Today's       Date" variable, and if it's true, proceed to the next step.
- Add an "Update Records" element to update the Opportunity record's stage to "Closed". You can also add a field update to update any other   fields  if needed.
- Save the flow and activate it.
Once the flow is activated, you can schedule it to run daily or at a specific time using a scheduler. This way, the flow will check if the Stop Sale date has passed and update the Opportunity record's stage to "Closed" if it has.
Note: Make sure to test the flow thoroughly in a sandbox environment before deploying it to a production environment.

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