Hello to all members out there.

I am very new to .net ado 

i am using visual studio to connect to oracle data base and insert records into a table.

my package and store procedure are as under 

CREATE OR REPLACE PACKAGE pkg_supplier
as
   PROCEDURE sp_insert_hpsuppliers(a_companyname IN VARCHAR2, a_contactname IN VARCHAR2, a_address IN VARCHAR2, a_city IN VARCHAR2);
end;
/

create or replace package body pkg_supplier
as
procedure sp_insert_hpsuppliers
(a_companyname in varchar2,a_contactname in varchar2,a_address in varchar2,a_city in varchar2)
as 
begin

insert into hp_suppliers values (a_companyname,a_contactname,a_address,a_city);
end sp_insert_hpsuppliers ;
end pkg_supplier;
/

and here is the code which i use to call store procedure

  ' Declare variables
        Dim li_rc As Integer
        Dim myString As String
        Dim myConn As New OleDb.OleDbConnection()

        ' Create new connection
        myString = "Provider=msdaora;Data Source=orcl;User Id=id;Password=pass;"
        Try
            myConn.ConnectionString = myString
            myConn.Open()
        Catch ex As OleDb.OleDbException
            MessageBox.Show(ex.Message)
            Exit Sub
        End Try

        ' CALL ACI SP
        Dim companyname As String
        Dim contactname As String
        Dim address As String
        Dim city As String

        companyname = TextBox1.Text
        contactname = TextBox2.Text
        address = TextBox3.Text
        city = TextBox4.Text

        Dim myCommand As New OleDb.OleDbCommand("pkg_supplier.sp_insert_hpsuppliers", myConn)
        myCommand.CommandType = CommandType.StoredProcedure



        Dim prmcompanyname As New OleDb.OleDbParameter()
        prmcompanyname.Direction = ParameterDirection.Input
        prmcompanyname.ParameterName = "a_companyname"
        prmcompanyname.Size = 50
        prmcompanyname.DbType = DbType.AnsiString
        myCommand.Parameters.Add(prmcompanyname)


        Dim prmcontactname As New OleDb.OleDbParameter()
        prmcontactname.Direction = ParameterDirection.Input
        prmcontactname.ParameterName = "a_contactname"
        prmcontactname.Size = 50
        prmcontactname.DbType = DbType.AnsiString
        myCommand.Parameters.Add(prmcontactname)



        Dim prmaddress As New OleDb.OleDbParameter()
        prmaddress.Direction = ParameterDirection.Input
        prmaddress.ParameterName = "a_address"
        prmaddress.Size = 50
        prmaddress.DbType = DbType.AnsiString
        myCommand.Parameters.Add(prmaddress)


        Dim prmcity As New OleDb.OleDbParameter()
        prmcity.Direction = ParameterDirection.Input
        prmcity.ParameterName = "a_city"
        prmcity.Size = 50
        prmcity.DbType = DbType.AnsiString
        myCommand.Parameters.Add(prmcity)

        Try
            li_rc = myCommand.ExecuteNonQuery()
            MessageBox.Show(li_rc & " Rows have been affected")
        Catch ex As Exception
            MessageBox.Show(ex.Message)
        End Try

        
    End Sub
End Class

i tried , checked many times but i am still getting an error message of 

ORA-06550: line 1, column 7: PLS-00306 ERROR!!

each time i run.

please help me with it and let me know where i am going worng.

Thanks