1 files changed, 1 insertions, 0 deletions
diff --git a/synapse/storage/databases/main/registration.py b/synapse/storage/databases/main/registration.py
index a6517962f6..5109ac174a 100644
--- a/synapse/storage/databases/main/registration.py
+++ b/synapse/storage/databases/main/registration.py
@@ -1091,6 +1091,7 @@ class RegistrationWorkerStore(CacheInvalidationWorkerStore):
                 delta equal to 10% of the validity period.
         """
         now_ms = self._clock.time_msec()
+        assert self._account_validity_period is not None
         expiration_ts = now_ms + self._account_validity_period
 
         if use_delta: