diff --git a/action.yml b/action.yml
index 6ba87835..1a29f336 100644
--- a/action.yml
+++ b/action.yml
@@ -58,7 +58,7 @@ runs:
           ARGS_INPUT+=("--check")
         fi
 
-        if [ ! -z "${{inputs.preserve-block-position}}" ]; then
+        if [ "${{inputs.preserve-block-position}}" = "true" ]; then
           ARGS_INPUT+=("--preserve-block-position")
         fi