System.Data.SqlServerCe.HashSafeHandle" could not release handle with value 0x08D7E430

Question

I am getting this error:

System.Data.SqlServerCe.HashSafeHandle" could not release handle with value 0x08D7E430

suddenly using

System.Data.SqlServer_Ce_unofficial 

and then calling this simple function (which worked all the time):

    Using nCmdSel As SqlServerCe.SqlCeCommand = uCn.CreateCommand
        With nCmdSel
            .CommandText = uCommandText
        End With

        Dim r As SqlServerCe.SqlCeDataReader = nCmdSel.ExecuteReader
        Return r

    End Using

Does anybody have any idea why?