diff --git a/synapse/appservice/api.py b/synapse/appservice/api.py

index 2ac1e13631..09104488f8 100644
--- a/synapse/appservice/api.py
+++ b/synapse/appservice/api.py
@@ -227,7 +227,9 @@ class ApplicationServiceApi(SimpleHttpClient):
 
         try:
             await self.put_json(
-                uri=uri, json_body=body, args={"access_token": service.hs_token},
+                uri=uri,
+                json_body=body,
+                args={"access_token": service.hs_token},
             )
             sent_transactions_counter.labels(service.id).inc()
             sent_events_counter.labels(service.id).inc(len(events))