diff --git a/enedisgateway2mqtt/rootfs/scripts/99-run.sh b/enedisgateway2mqtt/rootfs/scripts/99-run.sh
index 421ea96d2..c7008e594 100644
--- a/enedisgateway2mqtt/rootfs/scripts/99-run.sh
+++ b/enedisgateway2mqtt/rootfs/scripts/99-run.sh
@@ -42,7 +42,7 @@ if bashio::config.true "test"; then
     # Export all yaml entries as env variables
     # Helper function
     function parse_yaml {
-     local prefix=$2
+     local prefix=$2 || local prefix=""
      local s='[[:space:]]*' w='[a-zA-Z0-9_]*' fs=$(echo @|tr @ '\034')
      sed -ne "s|^\($s\):|\1|" \
         -e "s|^\($s\)\($w\)$s:$s[\"']\(.*\)[\"']$s\$|\1$fs\2$fs\3|p" \