Dryer won't run after stopping and"F" on digital

Dryer Repair
1

I have Kenmore Elite Oasis Canyon Capacity Electric Dryer - when I push start button it may run a few seconds and get the “F” code and continue to keep starting and sometimes will run for a few minutes and then stop or it may continue the cycle - sometimes you can feel the heat and sometimes it is just air??? They want you to call a Sears Repairman and last time I did that it cost me over $350
I cannot afford that at this time.

2

What is the F code. Also always remember sears sucks. Tom ApplianceEducator.com

3

Here is the tech sheet for this unit
https://www.servicematters.com/docs/wiring/Tech%20Sheet%20-%20W10035270.pdf