diff --git a/src/UseCases/UC_Booking/Commands/ExtendBookingDay.cs b/src/UseCases/UC_Booking/Commands/ExtendBookingDay.cs
index 50f77017..9c3a86ed 100644
--- a/src/UseCases/UC_Booking/Commands/ExtendBookingDay.cs
+++ b/src/UseCases/UC_Booking/Commands/ExtendBookingDay.cs
@@ -470,6 +470,7 @@ decimal oldTotalAmount
             booking.BasePrice = oldBasePrice;
             booking.PlatformFee = oldPlatformFee;
             booking.TotalAmount = oldTotalAmount;
+            booking.ExtensionAmount = null;
             booking.UpdatedAt = DateTimeOffset.UtcNow;
 
             // Revert contract dates