Want to use firstname from userinfo table instead of username from aspnetusers table in ASP.NET identity loggedin info in web form application

I have used ASP.NET Identity for Login and the table by default used in this is AspNetUsers. I have created separate UserInfo table with FirstName, LastName and UserId columns where UserId is the unique Identifier and referenced to AspNetUsers Id column table. Now, I want to display FirstName from UserInfo table instead of UserName from AspNetUsers.

<li><a runat="server" href="~/Account/Manage" title="Manage your account">Hi,  <%: Context.User.Identity.GetUserName() %></a></li>