diff --git a/board/mpl/common/flash.c b/board/mpl/common/flash.c
index 483d0ff..563039b 100644
--- a/board/mpl/common/flash.c
+++ b/board/mpl/common/flash.c
@@ -102,7 +102,7 @@
 #if CFG_MONITOR_BASE >= CFG_FLASH_BASE
 	flash_protect(FLAG_PROTECT_SET,
 			CFG_MONITOR_BASE,
-			CFG_MONITOR_BASE+CFG_MONITOR_LEN-1,
+			CFG_MONITOR_BASE+monitor_flash_len-1,
 			&flash_info[0]);
 #endif
 	size_b1 = 0 ;