If you are creating the table with OrmLite, the column for Language by default should be a string type (eg VARCHAR 255). And since En is your first member, it will be the default when not specified without any additional attributes. For example,
public class MyTable
{
[AutoIncrement]
public int Id { get; set; }
[Required]
public Language Language { get; set; }
}
db.CreateTableIfNotExists<MyTable>();
db.Insert(new MyTable());
// Inserted will be 1, "En"
Visuals from DataGrip:
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