Append characters to cell

I am trying to append character to a cell value for example c3 using following vb code.

For Each target As String In targetList
If target.Length > 1 AndAlso Char.IsLetter(target(0)) AndAlso Char.IsDigit(target(1)) Then
Dim columnIndex As Integer = Asc(target(0)) - Asc(“A”)
Dim rowIndex As Integer = Integer.Parse(target.Substring(1)) - 1
If rowIndex = row.Table.Rows.IndexOf(row) AndAlso columnIndex >= 0 AndAlso columnIndex < dt.Columns.Count Then
newRow(columnIndex) = characterToAdd & newRow(columnIndex).ToString()
End If
End If

The issue is instead of appending the character on c3 cell it is appending on c4.can someone help what i am missing

Hi @Pinky_AG

Can you share sample input and expected output.

Regards

I have a datatable which i am creating after reading excel file.

I want to append @ in the cell number C3 where the value is test. So apter append it will look like @test.

The above code is working but instead of adding @in the C3 cell it is appending @ in C4 cell

Hi @Pinky_AG

Can you share that datatable with dummy data.

Regards

Column1 column2 column3
Test rest 4/3/2024
Test1 rest1 4/3/2024
Hello next 4/3/3024

So i want to append @ on B3 cell which is rest1 but it is getting added in B4 @next