diff --git a/plugins/available/cmd-returned-notify.plugin.bash b/plugins/available/cmd-returned-notify.plugin.bash
index a3050875..d9be5e4e 100644
--- a/plugins/available/cmd-returned-notify.plugin.bash
+++ b/plugins/available/cmd-returned-notify.plugin.bash
@@ -9,7 +9,7 @@ precmd_return_notification() {
 }
 
 preexec_return_notification() {
-	[ -z "${LAST_COMMAND_TIME}" ] && export LAST_COMMAND_TIME=$(date +%s)
+	[[ -z "${LAST_COMMAND_TIME}" ]] && LAST_COMMAND_TIME=$(date +%s)
 }
 
 precmd_functions+=(precmd_return_notification)