Azure API - How do I setup CORS - asp.net

Question

I have REST API, that is hosted in Azure. If I make request in interactive console with GET method ('/api/pets'), request goes through just fine. But when I make POST request (POST '/api/pets'), CORS error appears.
Response in interacive console throws this error:
startup.cs
public void ConfigureServices(IServiceCollection services)
{
.
.
.
services.AddCors(options => options.AddPolicy("CorsPolicy",
builder =>
{
builder
.AllowAnyOrigin()
.AllowAnyHeader()
.AllowAnyMethod();
}));
.
.
.
}
public void Configure(IApplicationBuilder app, IWebHostEnvironment env)
{
app.UseCors("CorsPolicy");
.
.
.
}
All API's CORS policy
<policies>
<inbound>
<cors>
<allowed-origins>
<origin>*</origin>
</allowed-origins>
<allowed-methods preflight-result-max-age="300">
<method>GET</method>
<method>POST</method>
<method>PUT</method>
<method>DELETE</method>
<method>HEAD</method>
<method>OPTIONS</method>
<method>PATCH</method>
<method>TRACE</method>
</allowed-methods>
<allowed-headers>
<header>*</header>
</allowed-headers>
<expose-headers>
<header>*</header>
</expose-headers>
</cors>
</inbound>
<backend>
<forward-request />
</backend>
<outbound />
<on-error />
</policies>
I also tried setting CORS policy on azure portal only in specific API, but it doesn't work
Everything works fine locally.

Answer 1

Can you try configure this using the portal?
Open your API in the Azure API Management section of the Azure portal
Select All operations, or a single operation
On the right, choose Inbound processing > Add policy
You will get a list of prefab policy templates. Choose the "CORS" one and configure it at will:
UPDATE:
Can you modify the XML as below
<cors>
<allowed-origins>
<origin>*</origin>
</allowed-origins>
<allowed-methods>
<method>*</method>
</allowed-methods>
<allowed-headers>
<header>*</header>
</allowed-headers>
<expose-headers>
<header>*</header>
</expose-headers>
</cors>

Answer 2

Few years ago I tried Outboud rules into API Managment Policies to add this headers to response:
<policies>
<inbound>
<base />
<cors allow-credentials="true">
...
</cors>
</inbound>
...
<outbound>
<base />
<set-header name="Access-Control-Allow-Origin" exists-action="override">
<value>#(context.Request.Headers.GetValueOrDefault("Origin",""))</value>
</set-header>
<set-header name="Access-Control-Allow-Credentials" exists-action="override">
<value>true</value>
</set-header>
</outbound>
...
</policies>
Also make sure that you are using app.UseCors() before response compression if exists and before app.UseEndpoints() or app.UseMvc()