LG Dryer Model DLE2301R No heat but Heater Elements are working!

Replaced the high limit thermostat on the dryer and the dryer produced heat for a short while and then stopped producing heat.

I have not checked to see if the high limit thermostat is malfunctioning at this point but if it is, could something have caused it to malfunction as this was brand new and what should I be looking for?

Just don't want to put another high limit thermostat if something else that's causing the no heat scenario or the HI Limit to Malfunction again? Should I also be looking a Thermo Fuse

Any guidance here would be greatly appreciated... Jim B