.netcore web API Post does not work without SSL - asp.net-core

Question

I have an MVC core 2.2 application with Controllers, API controllers, and some Views. Some of the Views make use of the API endpoints within the same application. All was ok until I enabled TLS 1.2 in my windows server.
Now all endpoints decorated as GET methods work. But all POSTs have stopped working with chrome reporting this POST 'link' net::ERR_CONNECTION_RESET.
Other browsers catch exception at fail and display my error text with object
$.ajax({
url: "/api/Cart",
method: "post",
data: JSON.stringify(vm),
contentType: "application/json"
}).done(function(result) {
console.log(result);
}).fail(function(ex) {
console.log("Error occured while adding to cart" + ex)
});
I want to be able to POST even without SSL. I have disabled TLS 1.2 and restarted but still the same result.
If I browse the site with https://, POST and GET endpoints all work perfectly but if I browse with HTTP://, only GET endpoints work, all POST endpoints do not work.
I have combed the internet for almost 5 hours for something I thought would be simple.
public void ConfigureServices(IServiceCollection services)
{
var connectionString = Configuration.GetConnectionString("DataConnection");
services.AddDbContext<DataContext>(options => options.UseSqlServer(connectionString));
//Inject Connection String to other Classes
services.AddSingleton(_ => connectionString);
services.AddIdentity<ApplicationUser, IdentityRole>()
.AddEntityFrameworkStores<DataContext>()
.AddDefaultTokenProviders();
services.ConfigureApplicationCookie(options =>
{
options.Cookie.HttpOnly = true;
options.ExpireTimeSpan = TimeSpan.FromHours(1);
});
services.AddScoped<IUnitOfWork, UnitOfWork>();
services.AddMediatR(typeof(CreateProductCommand).Assembly, typeof(CreateProductCommandHandler).Assembly);
services.AddAutoMapper(typeof(MappingProfile));
// Add memory cache services
services.AddMemoryCache();
services.AddMvc(o =>
{
var policy = new AuthorizationPolicyBuilder()
.RequireAuthenticatedUser()
.Build();
o.Filters.Add(new AuthorizeFilter(policy));
}) .SetCompatibilityVersion(Microsoft.AspNetCore.Mvc.CompatibilityVersion.Version_2_2);
}
// HTTP request pipeline.
public void Configure(IApplicationBuilder app, IHostingEnvironment env)
{
if (env.IsDevelopment())
{
app.UseDeveloperExceptionPage();
app.UseDatabaseErrorPage();
}
else
{
app.UseExceptionHandler("/Home/Error");
}
var serviceProvider = app.ApplicationServices.GetRequiredService<IServiceScopeFactory>().CreateScope().ServiceProvider;
DataContextSeed.Initialize(serviceProvider);
app.UseStaticFiles();
app.UseAuthentication();
app.UseMvc(routes =>
{
routes.MapRoute(
name: "default",
template: "{controller=Home}/{action=Index}/{id?}");
});
}
Above is the Startup class and a sample post is here
[HttpPost]
public IActionResult Post([FromBody] SaleItemDTO md)
{
if(md != null)
{
if(md.Quantity <= md.Stock)
{
_sales.SalesPerson = User.Identity.Name;
_sales.SalesType = md.SalesType;
return Ok(_sales.ItemsInDb);
}
}
return BadRequest(new { Message = "Not Valid Content posted" });
}
Help with your thoughts.