diff --git a/src/Api.php b/src/Api.php
index 1ca9828..419afa7 100644
--- a/src/Api.php
+++ b/src/Api.php
@@ -494,7 +494,10 @@ class Api
 
     private function delete(string $url, string $error): void
     {
-        $response = $this->http()->delete($this->url.$url);
+        $response = $this->http()->withHeaders([
+            'content-type' => 'application/json',
+            'accept' => 'application/json',
+        ])->delete($this->url.$url);
 
         if (null === $response->json()) {
             $this->exception($error, $url, []);
diff --git a/src/Fakes/MembershipFake.php b/src/Fakes/MembershipFake.php
index 0f52c50..7f67a75 100644
--- a/src/Fakes/MembershipFake.php
+++ b/src/Fakes/MembershipFake.php
@@ -176,7 +176,7 @@ class MembershipFake extends Fake
     {
         $url = "https://nami.dpsg.de/ica/rest/nami/zugeordnete-taetigkeiten/filtered-for-navigation/gruppierung-mitglied/mitglied/{$memberId}/{$membershipId}";
         Http::assertSent(function ($request) use ($url) {
-            return $request->url() === $url && 'DELETE' === $request->method();
+            return $request->hasHeader('content-type', 'application/json') && $request->hasHeader('content-type', 'application/json') && $request->url() === $url && 'DELETE' === $request->method();
         });
     }