[Solved] ASP.Net GridView custom Pagination is not working in C#

There seem to be an issue with my GridView pagination, each time I click on the next page number or the "Next" button, it is either the GridView page skips or it returns back to GridView page "1".

Example: If I am on page 1, and I click on "Next" or I click on "2", it will show page "2" of the GridView. But when I continue and click on button "3" or "4", it will go back to page "1"

My GridView PageChange 

HTML

<div style="float: right; font-size: 10pt; margin-right: 1%;">
    Page&nbsp;
    <asp:Label ID="lblPageIndex" runat="server" Text="Label" />
    &nbsp;of&nbsp;
    <asp:Label ID="lblTotalPage" runat="server" />
    (<asp:Label ID="lblTotal" runat="server" />
    Records)&nbsp;&nbsp;
    <div class="dvPager">
        <asp:Repeater ID="rptPager" runat="server">
            <ItemTemplate>
                <asp:LinkButton ID="lnkPage" runat="server" Text='<%#Eval("Text") %>' CommandArgument='<%# Eval("Value") %>'
                    CssClass='<%# Convert.ToBoolean(Eval("Enabled")) ? "page_enabled" : "page_disabled" %>'
                    OnClick="Change_Page" OnClientClick='<%# !Convert.ToBoolean(Eval("Enabled")) ? "return false;" : "" %>'></asp:LinkButton>
            </ItemTemplate>
        </asp:Repeater>
    </div>
</div>

Code

protected void Change_Page(object sender, EventArgs e)
{
    int pageIndex = int.Parse((sender as LinkButton).CommandArgument);
    this.GetCustomersPageWise(pageIndex);
}

private void PopulatePager(int recordCount, int currentPage)
{
    double dblPageCount = (double)((decimal)recordCount / (decimal)PageSize);
    int pageCount = (int)Math.Ceiling(dblPageCount);
    List<System.Web.UI.WebControls.ListItem> pages = new List<System.Web.UI.WebControls.ListItem>();
    if (pageCount > 0)
    {
        if (currentPage != 1)
        {
            pages.Add(new System.Web.UI.WebControls.ListItem("Prev", (currentPage - 1).ToString()));
        }
        if (pageCount < 4)
        {
            for (int i = 1; i <= pageCount; i++)
            {
                pages.Add(new System.Web.UI.WebControls.ListItem(i.ToString(), i.ToString(), i != currentPage));
            }
        }
        else if (currentPage < 4)
        {
            for (int i = 1; i <= 4; i++)
            {
                pages.Add(new System.Web.UI.WebControls.ListItem(i.ToString(), i.ToString(), i != currentPage));
            }
            pages.Add(new System.Web.UI.WebControls.ListItem("...", (currentPage).ToString(), false));
        }
        else if (currentPage > pageCount - 4)
        {
            pages.Add(new System.Web.UI.WebControls.ListItem("...", (currentPage).ToString(), false));
            for (int i = currentPage - 1; i <= pageCount; i++)
            {
                pages.Add(new System.Web.UI.WebControls.ListItem(i.ToString(), i.ToString(), i != currentPage));
            }
        }
        else
        {
            pages.Add(new System.Web.UI.WebControls.ListItem("...", (currentPage).ToString(), false));
            for (int i = currentPage - 2; i <= currentPage + 2; i++)
            {
                pages.Add(new System.Web.UI.WebControls.ListItem(i.ToString(), i.ToString(), i != currentPage));
            }
            pages.Add(new System.Web.UI.WebControls.ListItem("...", (currentPage).ToString(), false));
        }
        if (currentPage != pageCount)
        {
            pages.Add(new System.Web.UI.WebControls.ListItem("Next", (currentPage + 1).ToString()));
        }
    }
    rptPager.DataSource = pages;
    rptPager.DataBind();

    lblPageIndex.Text = currentPage.ToString();
    lblTotalPage.Text = ((recordCount / PageSize) + ((recordCount % PageSize) > 0 ? 1 : 0)).ToString();
    lblTotal.Text = recordCount.ToString();
}

protected void OnPageIndexChanging(object sender, GridViewPageEventArgs e)
{
    GridView1.PageIndex = e.NewPageIndex;
    this.GetCustomersPageWise(1);
}

private void GetCustomersPageWise(int pageIndex)
{
    try
    {
        using (SqlConnection con = new SqlConnection())
        {
            con.ConnectionString = ConfigurationManager.ConnectionStrings["ConString"].ConnectionString;
            using (SqlCommand cmd = new SqlCommand("DataTable", con))
            {
                cmd.CommandType = CommandType.StoredProcedure;
                cmd.Parameters.AddWithValue("@CreatedBy", createby.Text.Trim());
                cmd.Parameters.AddWithValue("@PageIndex", pageIndex);
                cmd.Parameters.AddWithValue("@PageSize", PageSize);
                cmd.Parameters.Add("@RecordCount", SqlDbType.Int, 4);
                cmd.Parameters["@RecordCount"].Direction = ParameterDirection.Output;
                con.Open();
                using (SqlDataAdapter sda = new SqlDataAdapter())
                {
                    cmd.Connection = con;
                    sda.SelectCommand = cmd;
                    using (DataTable dt = new DataTable())
                    {
                        sda.Fill(dt);
                        using (SqlDataReader dr = cmd.ExecuteReader())
                            if (dr.HasRows)
                            {
                                Template.Visible = true;
                                GridView1.DataSource = dt;
                                GridView1.DataBind();
                            }
                            else
                            {
                                Template.Visible = false;
                            }
                        int recordCount = Convert.ToInt32(cmd.Parameters["@RecordCount"].Value);
                        this.PopulatePager(recordCount, pageIndex);
                    }
                }
                con.Close();
            }
        }
    }
    catch (SqlException ex)
    {
        string msg = "Error:";
        msg += ex.Message;
        throw new Exception(msg);
    }
}