diff --git a/jitsi_admin_application_dockerfile.txt b/jitsi_admin_application_dockerfile.txt
index affcd40..9cf94f1 100644
--- a/jitsi_admin_application_dockerfile.txt
+++ b/jitsi_admin_application_dockerfile.txt
@@ -1,8 +1,8 @@
 ARG VERSION
 ARG SUPERCRONIC_VERSION=0.2.33
-ARG PHP_ROOT_IMAGE_VERSION=3.20.5
+ARG PHP_IMAGE_VERSION=3.20.5
 
-FROM erseco/alpine-php-webserver:3.20.5
+FROM erseco/alpine-php-webserver:${PHP_IMAGE_VERSION}
 
 LABEL version="${VERSION}" \
     Maintainer="H2 invent GmbH" \