ASP.NET Core auth error, when using custom Login code

Question

I have a simple backend app. I have and endpoint called /notes for fetching notes. I have added RequireAuthorization() to it but I can't authorize the users. I have written the login and signup endpoints myself so that they send JWT tokens.

This is where I setup auth:

void ConfigAuth(WebApplicationBuilder builder)
{
    builder.Services.AddIdentityApiEndpoints<User>().AddEntityFrameworkStores<MyDBContext>();
    builder.Services.AddAuthentication().AddJwtBearer();
    builder.Services.AddAuthorization();
    builder
        .Services
        .AddAuthorizationBuilder()
        .AddPolicy("admin", policy => policy.RequireRole("admin"))
        .AddDefaultPolicy("user", policy => policy.RequireAuthenticatedUser());
}

This is the error I get after calling /notes route with authorization header:

Microsoft.Extensions.DependencyInjection.IdentityServiceCollectionExtensions+CompositeIdentityHandler[7]
Identity.BearerAndApplication was not authenticated. Failure message: Unprotected token failed

This is how I implement login: Link

Here is the link to my code in github: https://github.com/OmidNejadabbasi/notit-backend