diff --git a/minecraft-server/start b/minecraft-server/start
index 562f612c..77688f8c 100755
--- a/minecraft-server/start
+++ b/minecraft-server/start
@@ -8,7 +8,7 @@ if [ $(id -u) = 0 ]; then
     usermod -u $UID minecraft
   fi
   if [[ -v GID ]]; then
-    groupmod -g $GID minecraft
+    groupmod -o -g $GID minecraft
   fi
 
   if [[ $(stat -c "%u" /data) != $UID ]]; then