invoking (Excute, Call, etc) method every five minutes

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C#

ASP.NET

There are two pages on my website. Only the first page the user sees. User does not have access to the second page.The second page is never loaded.
But i have on the second page method called Add(), this method is in a folder called myfolder. How do I implement this method every five minutes.
I've used the following code but there is a problem.
Method is executed when the page is loaded condition. If you close this page, do not call this method at a time. While ASP.NET is running on, I did not stop in ASP.NET, I just close the browser screen.

What I want is that the method will automatically be applied during the day, even when the user does not open the page

<asp:Timer ID="Timer1" OnTick="Timer1_Tick" runat="server" Interval="300000" />
 
        <asp:UpdatePanel ID="UpdatePanell" runat="server" UpdateMode="Always">
        <Triggers>
            <asp:AsyncPostBackTrigger ControlID="Timer1"  EventName="Tick" />
        </Triggers>

protected void Timer1_Tick(object sender, EventArgs e)
       {
           myclass a=new myclass;
           a.Add();
       }