Trying to use Spring Boot REST to Read Request Body DTO with one property

Question

Here is my DTO

@Data
public class PermissionAddDto {
    @NotBlank
    private final String permName;
}

When I post this request

{
    "perm_name": "account_write"
}

It return an error :

JSON parse error: Cannot construct instance of com.hung.authentication.dtos.PermissionAddDto (although at least one Creator exists): cannot deserialize from Object value (no delegate- or property-based Creator); nested exception is com.fasterxml.jackson.databind.exc.MismatchedInputException: Cannot construct instance of com.hung.authentication.dtos.PermissionAddDto (although at least one Creator exists): cannot deserialize from Object value (no delegate- or property-based Creator)\n at [Source: (org.springframework.util.StreamUtils$NonClosingInputStream); line: 2, column: 5]

And I don't know why it not working . But when I add another property to my DTO , it works.