diff --git a/app/orm.py b/app/orm.py
index bbabbbc..71e3473 100644
--- a/app/orm.py
+++ b/app/orm.py
@@ -173,7 +173,7 @@ class Lease(Base):
         """
         renew = delta.total_seconds() * renewal_period
         renew = timedelta(seconds=renew)
-        return delta - renew
+        return delta + renew
 
 
 def init(engine: Engine):