[Solved] ASP.Net Menu not displaying horizontally in Production Server

Menu is not displaying horizontally in production.

<style type="text/css">
    body
    {
        font-family: Arial;
        font-size: 10pt;
    }
    .main_menu
    {
        width: 100px;
        background-color: #8AE0F2;
        color: #000;
        text-align: center;
        height: 30px;
        line-height: 30px;
        margin-right: 5px;
    }
    .level_menu
    {
        width: 110px;
        background-color: #000;
        color: #fff;
        text-align: center;
        height: 30px;
        line-height: 30px;
        margin-top: 5px;
    }
    .selected
    {
        background-color: #852B91;
        color: #fff;
    }
</style>
 
<form id="form1" runat="server">
    <asp:SiteMapDataSource ID="SiteMapDataSource1" runat="server" ShowStartingNode="false" />
    <asp:Menu ID="Menu" runat="server" Orientation="Horizontal"
        OnMenuItemDataBound="OnMenuItemDataBound"  DataSourceID="SiteMapDataSource1">
        <LevelMenuItemStyles>
            <asp:MenuItemStyle CssClass="main_menu" />
            <asp:MenuItemStyle CssClass="level_menu" />
        </LevelMenuItemStyles>
    </asp:Menu>
</form>

Recently we changed the server to Windows 2019. In Windows server 2016 it was working fine.