diff --git a/cmake_targets/tools/build_helper b/cmake_targets/tools/build_helper
index 9234358babc5dd98d4b49bc4170d058e946c76b8..f993ee50d652ca08759ef6d335a947569cc7375b 100755
--- a/cmake_targets/tools/build_helper
+++ b/cmake_targets/tools/build_helper
@@ -350,7 +350,7 @@ install_nas_tools() {
     echo_success "generate .ue_emm.nvram .ue.nvram"
     ./nvram --gen
   else
-    [ ./nvram -nt .ue.nvram  -o ./nvram -nt .ue_emm.nvram] && ./nvram --gen
+    [ ./nvram -nt .ue.nvram  -o ./nvram -nt .ue_emm.nvram ] && ./nvram --gen
   fi
 
   if [ ! -f .usim.nvram ]; then