diff --git a/supporting_material/update.sh b/supporting_material/update.sh
index c8fd0c6..a3ec4f2 100755
--- a/supporting_material/update.sh
+++ b/supporting_material/update.sh
@@ -1 +1 @@
-aws cloudformation create-stack --stack-name $1 --template-body file://$2  --parameters file://$3 --capabilities "CAPABILITY_IAM" "CAPABILITY_NAMED_IAM" --region=us-east-1
+aws cloudformation update-stack --stack-name $1 --template-body file://$2  --parameters file://$3 --capabilities "CAPABILITY_IAM" "CAPABILITY_NAMED_IAM" --region=us-east-1