diff --git a/alembic/versions/6ca3d74d51e4_move_state_store_to_main_database.py b/alembic/versions/6ca3d74d51e4_move_state_store_to_main_database.py
index 6a66c02d..b5cfe450 100644
--- a/alembic/versions/6ca3d74d51e4_move_state_store_to_main_database.py
+++ b/alembic/versions/6ca3d74d51e4_move_state_store_to_main_database.py
@@ -93,7 +93,7 @@ def upgrade():
     username_template = mxtg_config.get("bridge.username_template", "telegram_{userid}")
     hs_domain = mxtg_config["homeserver.domain"]
     localpart = username_template.format(userid="(.+)")
-    mxid_regex = re.compile(f"@{localpart}:{hs_domain}")
+    mxid_regex = re.compile("@{}:{}".format(localpart, hs_domain))
     for user in registrations:
         match = mxid_regex.match(user)
         if not match: