LG gas dryers have a more radical temp rise versus an electric model. They are VERY sensitive to long vent runs or any blockages. If you have a long vent run, any blockages, or both, when the flame is called upon to ignite the slowed airflow will increase the temp rise causing the unit too run shorter than normal. It may also leave a CO or GAS like smell behind, not having the proper airflow. Shorten your vent.