diff --git a/plugins/novatel.c b/plugins/novatel.c
index 3bd53edc..77caa7ed 100644
--- a/plugins/novatel.c
+++ b/plugins/novatel.c
@@ -66,6 +66,7 @@ static void novatel_remove(struct ofono_modem *modem)
 
 	ofono_modem_set_data(modem, NULL);
 
+	g_at_chat_unref(data->chat);
 	g_free(data);
 }
 
@@ -142,6 +143,8 @@ static int novatel_disable(struct ofono_modem *modem)
 	if (!data->chat)
 		return 0;
 
+	g_at_chat_cancel_all(data->chat);
+	g_at_chat_unregister_all(data->chat);
 	g_at_chat_send(data->chat, "AT+CFUN=0", NULL,
 					cfun_disable, modem, NULL);