diff --git a/infrastructure/userdata.sh b/infrastructure/userdata.sh
index e894352..db8a3e0 100644
--- a/infrastructure/userdata.sh
+++ b/infrastructure/userdata.sh
@@ -36,7 +36,7 @@ EOF
 crontab -u root -l >/dev/null 2>&1 || (echo "" | crontab -u root -)
 
 # Install and configure acme.sh
-curl https://get.acme.sh | sh -s email=${LEFTENCRYPT_EMAIL}
+curl https://get.acme.sh | sh -s email="${LETSENCRYPT_EMAIL}"
 
 # Configure acme.sh to use DNS API for FreeDNS
 . "/.acme.sh/acme.sh.env"