Dryer not drying cloths, heating element cycling off and on. element on for maybe 3 minutes and then off for 5 minutes. Looking at Thermostat-Sfty, loosing 240 volts on element when off.
You will want to check the venting from the blower wheel to the outside of your home first. If the venting checks ok and is clear of obstructions then you will want to check the cycling thermostat which may be cycling too quickly.