diff --git a/app/DataMapper/Tax/US/Rule.php b/app/DataMapper/Tax/US/Rule.php
index 24f65c9b5d..c1005a42cb 100644
--- a/app/DataMapper/Tax/US/Rule.php
+++ b/app/DataMapper/Tax/US/Rule.php
@@ -114,7 +114,7 @@ class Rule extends BaseRule implements RuleInterface
      */
     public function taxService($item): self
     {
-        if($this->tax_data?->txbService == 'Y') {
+        if(in_array($this->tax_data?->txbService,['Y','L'])) {
             $this->default($item);
         }
 
diff --git a/app/Http/Controllers/CompanyController.php b/app/Http/Controllers/CompanyController.php
index 108d0d74ab..a7900a3f17 100644
--- a/app/Http/Controllers/CompanyController.php
+++ b/app/Http/Controllers/CompanyController.php
@@ -418,7 +418,7 @@ class CompanyController extends BaseController
             $this->saveDocuments($request->input('documents'), $company, false);
         }
 
-        if($request->has('e_invoice_certificate')){
+        if($request->has('e_invoice_certificate') && !is_null($request->file("e_invoice_certificate"))){
 
             $company->e_invoice_certificate = base64_encode($request->file("e_invoice_certificate")->get());
             $company->save();
diff --git a/app/Http/Requests/Company/UpdateCompanyRequest.php b/app/Http/Requests/Company/UpdateCompanyRequest.php
index f4070350a8..602bb3a0fe 100644
--- a/app/Http/Requests/Company/UpdateCompanyRequest.php
+++ b/app/Http/Requests/Company/UpdateCompanyRequest.php
@@ -54,7 +54,7 @@ class UpdateCompanyRequest extends Request
         $rules['work_email'] = 'email|nullable';
         $rules['matomo_id'] = 'nullable|integer';
         $rules['e_invoice_certificate_passphrase'] = 'sometimes|nullable';
-        $rules['e_invoice_certificate'] = 'sometimes|file|mimes:p12,pfx,pem,cer,crt,der,txt,p7b,spc,bin';
+        $rules['e_invoice_certificate'] = 'sometimes|nullable|file|mimes:p12,pfx,pem,cer,crt,der,txt,p7b,spc,bin';
         // $rules['client_registration_fields'] = 'array';
 
         if (isset($input['portal_mode']) && ($input['portal_mode'] == 'domain' || $input['portal_mode'] == 'iframe')) {
diff --git a/tests/Feature/CompanyTest.php b/tests/Feature/CompanyTest.php
index a8eb0c8e89..af02f493ea 100644
--- a/tests/Feature/CompanyTest.php
+++ b/tests/Feature/CompanyTest.php
@@ -143,6 +143,8 @@ class CompanyTest extends TestCase
 
         $company->settings = $settings;
 
+        nlog($company->toArray());
+
         $response = $this->withHeaders([
             'X-API-SECRET' => config('ninja.api_secret'),
             'X-API-TOKEN' => $this->token,
diff --git a/tests/Unit/Tax/TaxConfigTest.php b/tests/Unit/Tax/TaxConfigTest.php
new file mode 100644
index 0000000000..df579795ad
--- /dev/null
+++ b/tests/Unit/Tax/TaxConfigTest.php
@@ -0,0 +1,71 @@
+<?php
+/**
+ * Invoice Ninja (https://invoiceninja.com).
+ *
+ * @link https://github.com/invoiceninja/invoiceninja source repository
+ *
+ * @copyright Copyright (c) 2021. Invoice Ninja LLC (https://invoiceninja.com)
+ *
+ * @license https://www.elastic.co/licensing/elastic-license
+ */
+
+namespace Tests\Unit\Tax;
+
+use Tests\TestCase;
+use App\Models\Client;
+use Tests\MockAccountData;
+use App\Services\Tax\Providers\TaxProvider;
+use Illuminate\Routing\Middleware\ThrottleRequests;
+use Illuminate\Foundation\Testing\DatabaseTransactions;
+
+/**
+ * @test App\Services\Tax\Providers\EuTax
+ */
+class TaxConfigTest extends TestCase
+{
+    use MockAccountData;
+    use DatabaseTransactions;
+    
+    protected function setUp() :void
+    {
+        parent::setUp();
+
+        $this->withoutMiddleware(
+            ThrottleRequests::class
+        );
+
+        $this->withoutExceptionHandling();
+
+        $this->makeTestData();
+
+        if(!config('services.tax.zip_tax.key'))
+            $this->markTestSkipped('No API keys to test with.');
+    }
+
+    public TaxProvider $tp;
+
+    private function bootApi(Client $client)
+    {
+        $this->tp = new TaxProvider($this->company, $client);
+    }
+
+    public function testStateResolution()
+    {
+        //infer state from zip
+        $client = Client::factory()->create([
+            'company_id' => $this->company->id,
+            'user_id' => $this->user->id,
+            'address1' => '400 Evelyn Pl',
+            'city' =>'Beverley Hills',
+            'state' =>'CA',
+            'postal_code' =>90210,
+            'country_id' => 840,
+        ]);
+
+        $this->bootApi($client);
+
+        $this->tp->updateClientTaxData();
+        
+    }
+
+}
\ No newline at end of file