1. From Setup, enter Activity Settings in the QuickFind box, then select Activity Settings.
2. Select Enable Creation of Recurring Tasks.
3. Click Submit.
4. Add the Create Recurring Series of Tasks field to the Task Detail section of your org’s Task page layouts.If the Salesforce Mobile and Lightning Experience Actions section on a Task page layout has been overridden, include the Delete Series and View Series actions from the Mobile & Lightning Actions category in the section. Add these actions if they’re not already there.To create recurring tasks in the Salesforce app, deselect Show simpler New Taskform on mobile on the Activity Settings page. The simpler New Task form doesn’t include the options for creating recurring tasks.