No. You will not be able to add a duplicate lead record. LeadSquared does not allow duplicate records. A lead record becomes duplicate if the same email Id (or any other field made unique in your account) is used for more than one lead. But you can add a lead with two different email id even though they have the same names. To know more, refer to How to Avoid Creating Duplicate Leads.
Can I add a duplicate Lead Record in LeadSquared?
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How to avoid creating duplicate task
Hello, Akshay.
While creating a new task type, you can configure the conflict option as Not Allowed to avoid creating more than one task in the same time slot. To know more, refer to Managing Task Types.