SQLite Encryption in Universal Windows Platform C# -

i'm using sqlite.net-pcl v 3.1.1 nuget package , vs extension sqlite universal windows platform 3.13.0.0. , code in windows 10 application in c# , xaml:

  private  void connecttodb()     {         var sqlpath = system.io.path.combine(windows.storage.applicationdata.current.localfolder.path, "persons.sqlite");          using (sqlite.net.sqliteconnection conn = new sqlite.net.sqliteconnection(new sqlite.net.platform.winrt.sqliteplatformwinrt(), sqlpath))         {             var res = conn.execute("pragma key = 'mypass'");              conn.createtable<person>();             conn.insert(person.newpersion());         }     }      public class person     {         public static person newpersion()         {             return new person() { uuid = guid.newguid().tostring(), name = "john", age = 12 };         }          [primarykey]         public string uuid { get; set; }         public string name { get; set; }         public int age { get; set; }     } 

this code works, creates db , inserts person. not working line

var res = conn.execute("pragma key = 'mypass'"); 

the weird thing 3 months ago got working, , trying open db without pragma key use throw:

'file encrypted or not database' 

which perfect because db encrypted. in fact trying open db generated in windows 10 sqliteexplorer throws exact error.

i need able encrypt db before, tried downloading previous libraries of extension , nuget no luck. manages encrypt sqlite db code?

regards.