The insured applies to renew his plan within 2 years from the date of first unpaid premium due date. (policybazaar.com)
The policy can also be revived within 2 years from the due date of first unpaid premium by paying all due but unpaid premiums with applicable interest. (myinsuranceclub.com)
However, the policy can be revived within 5 years from the due date of first unpaid premium. (coverfox.com)