diff --git a/distros/src/Dockerfile.apt-ubuntu b/distros/src/Dockerfile.apt-ubuntu
index 9f5e5bb9..08b65814 100644
--- a/distros/src/Dockerfile.apt-ubuntu
+++ b/distros/src/Dockerfile.apt-ubuntu
@@ -9,14 +9,12 @@ ENV \
   # LOCALE_INCLUDE="en"
 ARG TARGETPLATFORM
 ARG TYPE=core
-RUN echo "
-Acquire {\n\
+RUN echo "Acquire {\n\
   APT::Get::Allow-Unauthenticated \"true\";\n\
   GPG::Ignore \"true\";\n\
   AllowInsecureRepositories \"true\";\n\
   AllowDowngradeToInsecureRepositories \"true\";\n\
-}
-" > /etc/apt/apt.conf.d/skip-gpg-check-ig;
+}" > /etc/apt/apt.conf.d/skip-gpg-check-ig;
 RUN export DOMAIN="mirrors.ustc.edu.cn"; \
   test -z "$(echo $TARGETPLATFORM |grep arm)" && target=ubuntu || target=ubuntu-ports; \
   echo "deb http://${DOMAIN}/$target ${VER} main restricted universe multiverse" > /etc/apt/sources.list \