1 files changed, 1 insertions, 0 deletions

diff --git a/synapse/handlers/receipts.py b/synapse/handlers/receipts.py

index 726f7308d2..e536a909d0 100644
--- a/synapse/handlers/receipts.py
+++ b/synapse/handlers/receipts.py
@@ -156,6 +156,7 @@ class ReceiptsHandler(BaseHandler):
                             }
                         },
                     },
+                    key=(room_id, receipt_type, user_id),
                 )
 
     @defer.inlineCallbacks