ASP.NET Core 8.0 Web API not allowing me to get session objects when set from a fetch call using React

I have a React page that makes a request to stripe onboarding and stores the relevant data in sessions like this:

[HttpPost]
[Route("SignupSeller")]
public async Task<IActionResult> SignupSeller(SignupSellerInput signupSellerInput)
{
    StripeConfiguration.ApiKey = "xxxx";

    var optionsAccount = new AccountCreateOptions
        {
            Controller = new AccountControllerOptions
                             {
                                 Losses = new AccountControllerLossesOptions { Payments = "application" },
                                 Fees = new AccountControllerFeesOptions { Payer = "application" },
                                 StripeDashboard = new AccountControllerStripeDashboardOptions { Type = "express" },
                                 // RequirementCollection = "application",
                             },
            Capabilities = new AccountCapabilitiesOptions
                           {
                               CardPayments = new AccountCapabilitiesCardPaymentsOptions { Requested = true },
                               Transfers = new AccountCapabilitiesTransfersOptions { Requested = true },
                           },
            Email = signupSellerInput.email,
            BusinessType = "individual",
            Country = signupSellerInput.country,
        };

    var serviceAccount = new AccountService();
    Account account = serviceAccount.Create(optionsAccount);

    var optionsAccountLink = new AccountLinkCreateOptions
        {
            Account = account.Id,
            RefreshUrl = "http://localhost:3000/stripeerror",
            ReturnUrl = "http://localhost:3000/stripecomplete",
            Type = "account_onboarding",
            // CollectionOptions = new AccountLinkCollectionOptionsOptions
            //     {
            //         Fields = "currently_due",
            //     }, 
        };

    var serviceAccountLink = new AccountLinkService();
    AccountLink accountLink = serviceAccountLink.Create(optionsAccountLink);

    HttpContext.Session.SetString("accountId", account.Id);
    HttpContext.Session.SetString("accountEmail", signupSellerInput.email);
    HttpContext.Session.SetString("accountFirstName", signupSellerInput.firstname);
    HttpContext.Session.SetString("accountLastName", signupSellerInput.lastname);
    HttpContext.Session.SetString("accountBusinessName", signupSellerInput.businessname);
    HttpContext.Session.SetString("accountPaswword", signupSellerInput.password);
    HttpContext.Session.SetString("accountCountry", signupSellerInput.country);

    return Ok(new { accountLink = accountLink.Url });
}

When the success return url is called from stripe, I go to the StripeCompleted page which makes a fetch call to the Web API to store the information in my tables but the session objects are all null.

Like this:

[HttpPost]
[Route("StoreStripeAccount")]
public async Task<IActionResult> StoreStripeAccount()
{
    string accountId = HttpContext.Session.GetString("accountId");
    string accountEmail = HttpContext.Session.GetString("accountEmail");
    string firstname = HttpContext.Session.GetString("accountFirstName");
    string lastname = HttpContext.Session.GetString("accountLastName");
    string businessName = HttpContext.Session.GetString("accountBusinessName");
    string password = HttpContext.Session.GetString("accountPaswword");
    string country = HttpContext.Session.GetString("accountCountry");

    if (accountId != null && accountEmail != null)
    {
        String guidUser = Guid.NewGuid().ToString();

        TblUser user =  await userRepository.StoreUser(guidUser, accountEmail, password, firstname, lastname, businessName, country);

        stripeRepository.StoreConnectedAcount(user.Id, accountId);

        HttpContext.Session.Remove("accountId");
        HttpContext.Session.Remove("accountEmail");
        HttpContext.Session.Remove("accountFirstName");
        HttpContext.Session.Remove("accountLastName");
        HttpContext.Session.Remove("accountBusinessName");
        HttpContext.Session.Remove("accountPaswword");
        HttpContext.Session.Remove("accountCountry");

        return Ok(new { success = "accountAdded" });
    }
    else
    {
        return Ok(new { error = "couldNotAddAccount" });
    }
}

I have this in my Program.cs where the session timeout is set to 1 year>:

using Microsoft.EntityFrameworkCore;
using Microsoft.Extensions.Configuration;
using SoppingaWebAPI.Models;
using SoppingaWebAPI.Repository.Interface;
using SoppingaWebAPI.Repository.Services;
using System;

var builder = WebApplication.CreateBuilder(args);

// Add services to the container.

builder.Services.AddControllers();
// Learn more about configuring Swagger/OpenAPI at https://aka.ms/aspnetcore/swashbuckle
builder.Services.AddEndpointsApiExplorer();
builder.Services.AddSwaggerGen();

builder.Services.AddDistributedMemoryCache();

builder.Services.AddSession(options =>
    {
        options.IdleTimeout = TimeSpan.FromSeconds(31536000);
        options.Cookie.HttpOnly = true;
        options.Cookie.IsEssential = true;
    });

builder.Services.AddCors(options =>
    {
        options.AddPolicy("AllowAll", builder =>
        {
            builder.AllowAnyOrigin().AllowAnyMethod().AllowAnyHeader();
        });
    });

builder.Services.AddDbContext<SoppingaDbContext>(options =>
            options.UseSqlServer(builder.Configuration.GetConnectionString("DBConnection")));

builder.Services.AddScoped<IUserRepository, UserRepository>();
builder.Services.AddScoped<IStripeRepository, StripeRepository>();

var app = builder.Build();

// Configure the HTTP request pipeline.
if (app.Environment.IsDevelopment())
{
    app.UseSwagger();
    app.UseSwaggerUI();
}

app.UseDefaultFiles();
app.UseStaticFiles();

app.UseCors("AllowAll");
app.UseHttpsRedirection();

app.UseAuthorization();

app.UseSession();

app.MapControllers();

app.Run();

But all the sessions when trying to retrieve them are all null, where am I going wrong?