Hi @Vibhor_Dubey,
The manual marshaling and unmarshaling seems unnecessary based strictly on the example in the point you made. Maybe there’s further reason for it in your code, but you should definitely look at using BSON annotations so the marshaling and unmarshaling happens automagically:
@Divjot_Arora, are you able to glance over this and see if you can spot the point of failure in the code?