If you’re using the Experimental Custom FBW version. Just make sure you keep it updated everytime you start the Sim. They get updated sometimes 2x or up to 3x daily. So you have to keep updating it.
You can keep your aircraft to fly in managed airspeed. That way when you deploy the flaps, the Auto-thrust is already targeting a lower speed, which brings the thrust back to idle. That way, it can mitigate the extra lift generated by the flaps.