diff --git a/changelog.d/9195.bugfix b/changelog.d/9195.bugfix
new file mode 100644
index 000000000..5233ffc3e
--- /dev/null
+++ b/changelog.d/9195.bugfix
@@ -0,0 +1 @@
+Fix receipts or account data not being sent down sync. Introduced in v1.26.0rc1.
diff --git a/synapse/storage/databases/main/schema/delta/59/07shard_account_data_fix.sql b/synapse/storage/databases/main/schema/delta/59/07shard_account_data_fix.sql
new file mode 100644
index 000000000..9f2b5ebc5
--- /dev/null
+++ b/synapse/storage/databases/main/schema/delta/59/07shard_account_data_fix.sql
@@ -0,0 +1,18 @@
+/* Copyright 2021 The Matrix.org Foundation C.I.C
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *    http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+-- We incorrectly populated these, so we delete them and let the
+-- MultiWriterIdGenerator repopulate it.
+DELETE FROM stream_positions WHERE stream_name = 'receipts' OR stream_name = 'account_data';
diff --git a/synapse/storage/util/sequence.py b/synapse/storage/util/sequence.py
index b6fe136fb..c780ade07 100644
--- a/synapse/storage/util/sequence.py
+++ b/synapse/storage/util/sequence.py
@@ -180,7 +180,7 @@ class PostgresSequenceGenerator(SequenceGenerator):
         if max_in_stream_positions and max_in_stream_positions > last_value:
             raise IncorrectDatabaseSetup(
                 _INCONSISTENT_STREAM_ERROR
-                % {"seq": self._sequence_name, "stream": stream_name}
+                % {"seq": self._sequence_name, "stream_name": stream_name}
             )