Angular 9 on refresh url redirects to https on production

Question

I am using angular 9, the issue I am facing on production is that, when ever I refresh page on browser it goes to https://subdomain.example.com/orders from http://subdomain.example.com/orders . I do not want to use ssl for subdomain. This issue is happening only for urls that point to OrdersModule and ShipmentsModule.

What am I missing here?

app-routing.module.ts

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { LoginComponent }  from './login/login.component';
import { DashboardComponent }  from './dashboard/dashboard.component';
import { AuthGuard } from './authguard';
import { CalendarComponent } from './calendar/calendar.component';
import { CouponsComponent } from './coupons/coupons.component';


const routes: Routes = [
  { path: 'login', component: LoginComponent },
  { path: 'orders', loadChildren: () => import('./orders/orders.module').then(m => m.OrdersModule), canActivate: [AuthGuard]},
  { path: 'calendar', component: CalendarComponent, canActivate: [AuthGuard] },
  { path: 'coupons', component: CouponsComponent, canActivate: [AuthGuard] },
  { path: 'shipments', loadChildren: () => import('./shipments/shipments.module').then(m => m.ShipmentsModule), canActivate: [AuthGuard] },
  { path: '', component: DashboardComponent, canActivate: [AuthGuard] },
];

@NgModule({
  imports: [RouterModule.forRoot(routes)],
  exports: [RouterModule]
})
export class AppRoutingModule { } 

shipments-routing.module.ts

import { NgModule } from '@angular/core';
import { Routes, RouterModule } from '@angular/router';
import { ShipmentsComponent } from './shipments.component';
import {ShipmentsAddComponent} from './shipments-add/shipments-add.component';


const routes: Routes = [
  { path: '', component: ShipmentsComponent },
  { path: 'add', component: ShipmentsAddComponent },
];

@NgModule({
  imports: [RouterModule.forChild(routes)],
  exports: [RouterModule]
})
export class ShipmentsRoutingModule { }

.htaccess RewriteEngine On

RewriteCond %{DOCUMENT_ROOT}%{REQUEST_URI} -f [OR]

RewriteCond %{DOCUMENT_ROOT}%{REQUEST_URI} -d

RewriteRule ^ - [L]

RewriteRule ^ /index.html

Answer 1

The issue was Strict-Transport-Security it was true for all subdomains.

Adding line below to main domain's .htaccess file solved the issue

Header always unset Strict-Transport-Security