issue when validating the signed invoice with the compliance API

Signing process
1

Hello,
I’m facing an issue when validating the signed invoice with the compliance API.
The error returned is:
The invoice hash API body does not match the (calculated) Hash of the XML
Details:

  • The XML invoice is generated and signed according to ZATCA Phase 2 requirements.

  • After signing, I calculate the invoice hash and send it in the API body.

  • However, the compliance check returns the above error, meaning the API’s calculated hash doesn’t match mine.
    HERE IS MY CODE .NET

    private async Task TestForCompliance(string invoice, EGSUnit egsUnit, CSID complianceCSID, CancellationToken cancellationToken)
    {
    string id = Guid.NewGuid().ToString();
    var invoiceForEGS = invoice
    .Replace(“EGS_UUID”, id)
    .Replace(“VAT_NUMBER”, egsUnit.VAT.RegistrationNumber)
    .Replace(“VAT_NAME”, egsUnit.VAT.Name);

       var signed = Crypto.SignInvoice(invoiceForEGS, complianceCSID.BinarySecurityToken, egsUnit.PrivateKey);

   // هنا نستخدم الـ UUID اللي فعلياً في الفاتورة الموقعة
   return await \_zatcaApiService.ComplianceCheck(
                    signed.UniqueInvoiceId,
                   egsUnit,
                  complianceCSID,
                  signed.Invoice,  // XML النهائي
                  signed.Hash,     // الهاش النهائي المتوافق
                   cancellationToken

    );
    }
    public async Task ComplianceCheck(string uuid,EGSUnit egsUnit, CSID complianceCSID, string signedInvoice, string invoiceHash, CancellationToken cancellationToken = default)
    {
    SetPortal(egsUnit);
    _ = complianceCSID ?? throw new ArgumentNullException(“Compliance CSID not found.\n\r Compliance CSID must be generated before compliance checks”);
    var content = JsonContent.Create(new
    {
    Uuid = uuid,
    InvoiceHash = invoiceHash,
    Invoice = Convert.ToBase64String(Encoding.UTF8.GetBytes(signedInvoice))
    });
    AddAuthHeader(complianceCSID);
    return await GetResponseWithRetry(() => _httpClient.PostAsync(“compliance/invoices”, content, cancellationToken), result => result.IsSuccessStatusCode || result.StatusCode == System.Net.HttpStatusCode.BadRequest);
    }