How can one avoid capturing leading empty or blank lines?

the data  I deal with look like this

"will be paid on the dates you specified.

xyz supplier [123445797891]
 amount: $100.52   when: September 07, 2007   reference #: 0415
 from: operating account [236424735]

abc, Jane'S CHOICE [0089456881545]
 amount: $487.61   when: September 08, 2007   reference #: 0416
 from: finess [0236454514]

"
regexoptions are:
multi-line,explict capture, ignorecase, dotall, ignore pattern white space

regex expression used for capturing
(?<AcctName>^\w*,{0,1}(\s\w*('s){0,1},{0,1})*)\s\[(?<AcctNbr>\d*)\].{4,8}amo
unt:\s\$(?<Amt>\b[0-9][0-9,]*\.\d\d)\s*when:\s*(?<Dt2Pay>[ADFJMNOS][aceopu][
bcglnprtvy][ya-v]{0,9}\s\d{1,2},\s\d\d\d\d\b)\s*reference\s*\#\:\s*(?<RefNbr

*)\]

the exrpession used in Result(strGrps)
${AcctName} ${Amt} ${Dt2Pay} ${RefNbr} PCF ${FromAcctName} ${FromAcctNbr}
Result is
"
xyz supplier 100.52 September 07, 2007 0415 PCF operating account 236424735

abc, PRESIDENT'S CHOICE 487.61 September 08, 2007 0416 PCF finess
0236454514"
However desired result are lines with columns tab delimited and without
extra leading lines:
"xyz supplier 100.52 September 07, 2007 0415 PCF operating account 236424735
abc, PRESIDENT'S CHOICE 487.61 September 08, 2007 0416 PCF finess
0236454514"

what do I have to adjust in the regex expresiion?

or Do I have to change the codes used?:

           // compile
           string strRegex = textBoxRegex.Text;
           bool bCompiled = false;
           bool bCompiled = false;

           try
           {

       RegexOptions regexOptn = RegexOptions.Singleline

RegexOptions.ExplicitCapture | RegexOptions.IgnorePatternWhitespace
               myRegex = new Regex(strRegex, regexOptn);  // try compile
with options
               bCompiled = true;
               bMatched = false;
               setStatusText("Regex Compiled.");
           }
           catch (Exception ex)
           {
               setMsg("Error in regex compilation or combination of regex
options. " + ex.Message);

           }

// match

   MatchCollection myMatch = null;
   if (bCompiled ) {
               myMatch = myRegex.Matches(textBoxInput.Text);
   }
// capturing result
   if (myMatch.Count > 0) {
           string strMatchGrpVarName = textBoxGroupName.Text.Replace(",", "
");
           int i  = 0;
           bool bSuccess = false;

           if (myMatch.Count <= 0 ) { setStatusText("No match Found");
return bSuccess;  }
           string mybuf = "";

           //int iCapBeg = myMatch.Captures.
           foreach (Match match in myMatch)
           {
               i++;
               if (i == 1) {
                   mybuf = match.Result(strMatchGrpVarName);
                   if (bSingle) break;
               } else {
                   string strResult = "";
                   mybuf += csCrLf + match.Result(strMatchGrpVarName);
               }
               match.NextMatch();
               if (bSingle) break;
           }
           MessageBox.Show("count=" + strMatchGrpName.Length + csCrLf +
mybuf);
}

thank you for your time and expertise