After using Defaultbuilder to register valid json, why is the object immediately null?

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There could be several reasons why the object is immediately null:

1. Invalid JSON: If the JSON that was registered is invalid, then the object will be null. Check if the JSON is properly formatted and does not have any syntax errors.
2. Incorrect object mapping: If the object mapping is incorrect, then the object will be null. Check if the properties in the JSON matches the properties in the model class.
3. Empty JSON: If the JSON is empty, then the object will be null. Make sure there is valid content in the JSON.
4. Incorrect use of Defaultbuilder: If the Defaultbuilder is not used correctly, then the object will be null. Make sure the code is properly written and executed.