Filling a predefined table in word template by C#

I am trying to create a bill say a mobile customized bill, to make it good looking I am using word template and merge fields to fill the values occuring once only, like customer name, bill period, date etc. but to show customized bill I need to populate the bill detail in the same word doc.
Somehow like this

<>><> <>

Number	Duration	Call(s)	Cost

<>

>

I am able to replace the fields CustomerName, MobileNumber, BillPeriod, Date by using below code

  foreach (Word.Field myMergeField in myWordDoc.Fields)

                {

                    Word.Range rngFieldCode = myMergeField.Result;

                    String fieldText = rngFieldCode.Text;

                    if (fieldText.StartsWith(" MERGEFIELD"))

                    {

                        Int32 endMerge = fieldText.IndexOf("\\");

                        Int32 fieldNameLength = fieldText.Length - endMerge;

                        String fieldName = fieldText.Substring(11, endMerge - 11);                     

                        foreach (DataColumn dc in dt.Columns)

                        {

                            if (fieldName == dc.ColumnName)

                            {

                                myMergeField.Select();

                                myWordApp.Selection.TypeText(dt.Rows[0][dc.ColumnName].ToString());

                                

                            }

                        }

                    }

                }
But not able to fill the data in datatable, can someone please help me to fill the data in the table, please help me with C# code and the format I need to place in template file. Please avoid suggestion for tools like aspose etc.