Columnset

Hello

I am facing problem in setting the columnset dynamically in ultratree,

Ex: I am modifing the node's columnset in one of the events after the initial columnset is set
for (int i = 0; i < nodes.Length && nodes[i] != "value"; i++)
                        {
                           
                            node = GetNode();
                        }
                        if (mapEntry.stringarray == null)
                        {
                            node.Cells["Value"].EditorComponent = GetVariableParameter();
                            node.Override.ColumnSet = this.Criterias.CriteriaTree.ColumnSettings.ColumnSets["STRING"];
                            node.Cells["Value"].Value = mapEntry.@string[1];
                        }
//Designer
            ultraTreeNodeColumn31.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.ActivateOnly;
            ultraTreeNodeColumn31.DataType = typeof(string);
            ultraTreeNodeColumn31.Key = "Err";
            ultraTreeNodeColumn31.LayoutInfo.PreferredCellSize = new System.Drawing.Size(26, 24);
            ultraTreeNodeColumn32.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.ActivateOnly;
            ultraTreeNodeColumn32.Key = "Field";
            ultraTreeNodeColumn32.LayoutInfo.PreferredCellSize = new System.Drawing.Size(200, 24);
            ultraTreeNodeColumn33.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.Full;
            ultraTreeNodeColumn33.DataType = typeof(string);
            ultraTreeNodeColumn33.Key = "Operator";
            ultraTreeNodeColumn33.LayoutInfo.PreferredCellSize = new System.Drawing.Size(100, 24);
            ultraTreeNodeColumn34.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.Full;
            ultraTreeNodeColumn34.DataType = typeof(string);
            ultraTreeNodeColumn34.Key = "Value";
            ultraTreeNodeColumn34.LayoutInfo.PreferredCellSize = new System.Drawing.Size(150, 24);
            ultraTreeNodeColumn35.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.Full;
            ultraTreeNodeColumn35.DataType = typeof(bool);
            ultraTreeNodeColumn35.Key = "Ask";
            ultraTreeNodeColumn35.LayoutInfo.PreferredCellSize = new System.Drawing.Size(40, 24);
            ultraTreeNodeColumn36.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.Full;
            ultraTreeNodeColumn36.Key = "Remove";
            ultraTreeNodeColumn36.LayoutInfo.PreferredCellSize = new System.Drawing.Size(75, 24);
            ultraTreeNodeColumn54.Key = "Temp";
            ultraTreeNodeColumn54.Visible = false;
            ultraTreeColumnSet6.Columns.Add(ultraTreeNodeColumn31);
            ultraTreeColumnSet6.Columns.Add(ultraTreeNodeColumn32);
            ultraTreeColumnSet6.Columns.Add(ultraTreeNodeColumn33);
            ultraTreeColumnSet6.Columns.Add(ultraTreeNodeColumn34);
            ultraTreeColumnSet6.Columns.Add(ultraTreeNodeColumn35);
            ultraTreeColumnSet6.Columns.Add(ultraTreeNodeColumn36);
            ultraTreeColumnSet6.Columns.Add(ultraTreeNodeColumn54);
            ultraTreeColumnSet6.Key = "STRING";
            ultraTreeNodeColumn19.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.ActivateOnly;
            ultraTreeNodeColumn19.Key = "Err";
            ultraTreeNodeColumn19.LayoutInfo.PreferredCellSize = new System.Drawing.Size(26, 24);
            ultraTreeNodeColumn20.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.ActivateOnly;
            ultraTreeNodeColumn20.Key = "Field";
            ultraTreeNodeColumn20.LayoutInfo.PreferredCellSize = new System.Drawing.Size(200, 24);
            ultraTreeNodeColumn21.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.Full;
            ultraTreeNodeColumn21.Key = "Operator";
            ultraTreeNodeColumn21.LayoutInfo.PreferredCellSize = new System.Drawing.Size(100, 24);
            ultraTreeNodeColumn22.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.Full;
            ultraTreeNodeColumn22.DataType = typeof(System.DateTime);
            ultraTreeNodeColumn22.Format = "dd/MM/yyyy hh:mm:ss";
            ultraTreeNodeColumn22.FormatProvider = new System.Globalization.CultureInfo("fr-FR");
            ultraTreeNodeColumn22.Key = "Value";
            ultraTreeNodeColumn22.LayoutInfo.PreferredCellSize = new System.Drawing.Size(150, 24);
            ultraTreeNodeColumn23.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.Full;
            ultraTreeNodeColumn23.DataType = typeof(bool);
            ultraTreeNodeColumn23.Key = "Ask";
            ultraTreeNodeColumn23.LayoutInfo.PreferredCellSize = new System.Drawing.Size(40, 24);
            ultraTreeNodeColumn24.AllowCellEdit = Infragistics.Win.UltraWinTree.AllowCellEdit.Full;
            ultraTreeNodeColumn24.Key = "Remove";
            ultraTreeNodeColumn24.LayoutInfo.PreferredCellSize = new System.Drawing.Size(75, 24);
            ultraTreeNodeColumn52.Key = "Temp";
            ultraTreeNodeColumn52.Visible = false;
            ultraTreeColumnSet4.Columns.Add(ultraTreeNodeColumn19);
            ultraTreeColumnSet4.Columns.Add(ultraTreeNodeColumn20);
            ultraTreeColumnSet4.Columns.Add(ultraTreeNodeColumn21);
            ultraTreeColumnSet4.Columns.Add(ultraTreeNodeColumn22);
            ultraTreeColumnSet4.Columns.Add(ultraTreeNodeColumn23);
            ultraTreeColumnSet4.Columns.Add(ultraTreeNodeColumn24);
            ultraTreeColumnSet4.Columns.Add(ultraTreeNodeColumn52);
            ultraTreeColumnSet4.Key = "DATETIME";

before assigning the column set["STRING"] , node had "DATETIME" as columnset value
After assigning though its displaying columnset as ["STRING"], its datatype is still "DateTime"

Could you please help me out?