diff --git a/pretix_matrix_inviter/tasks.py b/pretix_matrix_inviter/tasks.py
index 8b45ef05ff2fd40de3f30e76679eaac19b6b4b00..e1af05dd2f85b370835560a89672cdcb64356595 100644
--- a/pretix_matrix_inviter/tasks.py
+++ b/pretix_matrix_inviter/tasks.py
@@ -51,22 +51,20 @@ def matrix_inviter_invite(
         r.raise_for_status()
     except (requests.ConnectionError, requests.HTTPError) as e:
         if r.status_code in (400, 403):
-            response_dump = r.json()
             order.log_action(
                 "pretix_matrix_inviter.error",
                 data={
                     "matrix_id": user_matrix_id,
                     "matrix_room": room_matrix_id,
                     "error": "HTTP Code {} ({})".format(
-                        r.status_code, response_dump["error"]
+                        r.status_code, r.json()["error"]
                     ),
                 },
             )
         else:
             try:
                 if r.status_code == 429:
-                    response_dump = r.json()
-                    backoff = response_dump["retry_after_ms"] / 1000
+                    backoff = r.json()["retry_after_ms"] / 1000
                     self.retry(countdown=backoff)
                 else:
                     self.retry()