diff --git a/alpine/5/Dockerfile b/alpine/5/Dockerfile
index 1a726fc..24e31f3 100644
--- a/alpine/5/Dockerfile
+++ b/alpine/5/Dockerfile
@@ -28,7 +28,7 @@ RUN npm install --production \
     && mv /var/www/app/public $BAK_PUBLIC_PATH  
 
 # Prepare php image
-FROM php:${PHP_VERSION}-fpm-alpine as prod
+FROM php:${PHP_VERSION}-fpm-alpine3.13 as prod
 ARG INVOICENINJA_VERSION
 ARG BAK_STORAGE_PATH
 ARG BAK_PUBLIC_PATH