Hero Engine Destini's engine is seized but can be repaired at service center. Now is it safe to used or not? Or exchange with new scooter?

If the scooter is repairable and in good condition for use, then you may continue to use your Hero Destini. Moreover, exchange of a vehicle would depend on certain factors such as kilometres driven, physical condition, number of owners, etc. For detailed information, we would request you to please connect with the nearest authorized dealership in your city.