To initiate a scheduled invoice generation, an Autolaunched Flow invoking the Invoice API invocable class should be created where the flow will be called in a Batch Job.
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Go to Setup.
In the Quick Find box, search and select Batch Management.
Click New.
Enter some required data and click the autolaunch flow that’s been created a while ago and click Next. In next screen, select the recordId as Flow Input Variable and Opportunity as Object
Note: The required batch size would be 60 only to prevent hitting the governor limit
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Click Save.
Create a Schedule Flow
Follow the steps on how to create an Autolaunched Flow invoking the Invoice API invocable class:a Scheduled-Triggered Flow
Go to Setup.
In the Quick Find box, search and select Flows.
Click New Flow.
In the New Flow modal, select Scheduled-Triggered Flow.
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Set the date, time, and frequency.
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Drag an action and find the batch name that you created a while ago in batch management and select it.
7. Click Save and activate.
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