AutoLogin to Report Server while accessing SSRS Reports using ngx-ssrs-reportviewer

I am having ssrs report server credentials. I want the users to auto login (impersonate) whenever they go to the reports page using the credentials that I have hard coded. I am using ngx-ssrs-reportviewer plugin in angular 8 and I am using asp.net core 3.0 as backend.

I have set the credentials from web api services. Here is the code:

                ReportingService2005SoapClient rs = new ReportingService2005SoapClient(EndpointConfiguration.ReportingService2005Soap);
                rs.ClientCredentials.Windows.ClientCredential = new System.Net.NetworkCredential(ConfigurationManager.AppSettings["SSRS:UserName"], ConfigurationManager.AppSettings["SSRS:Password"], ConfigurationManager.AppSettings["SSRS:Domain"]);
                rs.ClientCredentials.Windows.AllowedImpersonationLevel = System.Security.Principal.TokenImpersonationLevel.Impersonation;

Here is the alert box that I don't want to display to the users: alert box