You have to fill up cancellation letter return your policy back and write the cause of it. For this, you can contact in any branch or say to return back the policy by a phone call to call center. Call center will forward your document, but you have to fill up cancellation letter necessarily and return real documents.
Insurance company returns back your premium amount within 7 days. Some expenditure like fee of examining medical fitness, Stamp duty, and service charge will be subtracted from the amount of premium.
The time of free look period starts from the day you have got documents of policy. Normally documents of policy are received during 15 days from applying for the policy.
In ‘free look period’ you get time to understand the ins and outs of policies. Generally the documents of policies are very long and it is not easy to understand them. So it will be better that contact your agent and try to understand the policy.