Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Cannot convert null literal to non-nullable reference type.

Converting null literal or possible null value to non-nullable type.

Possible null reference assignment.

Possible null reference argument for parameter 'value' in 'JsonNode.explicit operator int(JsonNode value)'.

Non-nullable property 'msg' must contain a non-null value when exiting constructor. Consider declaring the property as nullable.