Our dryer stopped heating so we changed element and cutoff kit, worked for 2 loads and quit, again changed cutoff kit and worked for 15 minutes and stopped heating again, what are we not doing right?

Have you reached into the back the dryer's vent port? Most will just replace the hose but fail to clean out the dryer's internal vent tube from the internal blower.

Re-check the fuse, a clogged internal vent tube will blow the fuse again.

You need to change the thermal cutoff and hi-limit also. Here are those parts to order.
Thermal cutoff kit.
Hi-limit thermostat.

All parts come with a 365 day, any part, any reason return policy.

Do all again

you might have a venting problem or is the element grounded???

There's a thermostat on the vent. That's the one you would need to change.

Yes it is. It is more than likely your high limit thermostat. The high limit thermostat is located on the back of the dryer after the heating element, (right before the entrance into the drying chamber). They high limit and thermal cutoff usually come as a kit because they should be replaced at the same time. The thermal cutoff is located on or around the body of the heating element. good luck!

Make sure lint filter is clean also frre airflow from Exhaust, if tisis ok could be thermostat or element, try basic stuff 1st...

check the thermo again, it might be going out due to a short in the element, or obstructed venting causing too much heat, clear venting or replace therm/heating element if needed.

check the in-line limiters on the heating coil tube.

Zuraxus what you are seeing is normal for a time. Here is how this dryer works. With a wet towel in the dryer, the first 5 minutes is testing to see if the load is wet. If so then between 5 & 10 minutes the dryer will turn on the 800 watt heater section (only in clockwise rotation). If still wet enough from 10 minutes to 15 minutes it will turn on the 1900 watt heater (heating only in clockwise). If still wet enough 15 to dry will turn on the full 2700 watts in clockwise and 800 watts in counter clock wise. That is how the cycle works. However it is hard to tell with the rear cover removed as the blower pushes the air thru the heater. Careful that by running with the back panel off you don't trip the high temp manual reset protector. So yes this sounds normal. What is the issue that is causing you to think the dryer isn't working proper?