Database FIrebird Error

1. public int Save(Pegawai PG)  
2.        {  
3.            using (FbCommand cmd = conn.CreateCommand())  
4.            {  
5.                cmd.CommandText = "Simpanpegawai";  
6.                cmd.CommandType = System.Data.CommandType.StoredProcedure;  
7.                cmd.Parameters.AddWithValue("KodePelanggan", FbDbType.VarChar).Value = PG.KodePegawai;  
8.                cmd.Parameters.AddWithValue("Nama", FbDbType.VarChar).Value = PG.Nama;  
9.                cmd.Parameters.AddWithValue("TempatLahir", FbDbType.VarChar).Value = PG.TempatLahir;  
10.                cmd.Parameters.AddWithValue("TanggalLahir", FbDbType.Date).Value = PG.TanggalLahir; //Masukkan Dengan Format Tanggal "dd/mm/yyyy"  
11.                cmd.Parameters.AddWithValue("JenisKelamin", FbDbType.VarChar).Value = PG.JenisKelamin;  
12.                cmd.Parameters.AddWithValue("Alamat", FbDbType.VarChar).Value = PG.Alamat;  
13.                cmd.Parameters.AddWithValue("Telp", FbDbType.Numeric).Value = PG.Telp;  
14.                cmd.Parameters.AddWithValue("HP", FbDbType.Numeric).Value = PG.HP;  
15.                cmd.Parameters.AddWithValue("Pendidikan", FbDbType.VarChar).Value = PG.Pendidikan;  
16.                cmd.Parameters.AddWithValue("IDJabatan", FbDbType.Integer).Value = PG.IDJabatan;  
17.                cmd.Parameters.AddWithValue("NoRek", FbDbType.Numeric).Value = PG.NoRek;  
18.                cmd.Parameters.AddWithValue("TanggalMasuk", FbDbType.Date).Value = PG.TanggalMasuk; //Masukkan Dengan Format Tanggal "dd/mm/yyyy"  
19.                cmd.Parameters.AddWithValue("TanggalKeluar", FbDbType.Date).Value = PG.TanggalKeluar; //Masukkan Dengan Format Tanggal "dd/mm/yyyy"  
20.                cmd.Parameters.AddWithValue("Foto", FbDbType.VarChar).Value = PG.Foto;  
21.                cmd.Parameters.AddWithValue("Keterangan", FbDbType.VarChar).Value = PG.Keterangan;  
22.                return cmd.ExecuteNonQuery();  
23.            }  
24.        } 
    

error:

An unhandled exception of type 'System.FormatException' occurred in FirebirdSql.Data.FirebirdClient.dll  Additional information: String was not recognized as a valid DateTime.