Re ignite pilot light

The limit switch is bad. most likely or the igniter. Does it give off a gas smell? If it is propane you can really smell it. But Natural Gas You may not.

Switch the gas valve to pilot then hold down the red button and light the gas with a flame then hold it down for at least 1 min then release the button and switch the gas valve to on.

I agree. It's rotten to have someone check out your product and then have it stop working. You probably have a problem with your ignition panel.This is the part of gas dryers that gets hot. When it reaches a certain temperature it causes the pilot light to ignite. It sounds as if your ignition needs to be replaced. We did this and had another 6 years from our gas dryer.
If you're handy you can probably do this replacement yourself. If you're like my spouse and me, we found a reasonably priced professional who completed it in just a few minutes.
Good luck. I hope this helps you. If it does, please come back to Fixya and rate my help!

Sounds like the igniter needs to be replaced. It is normal for a heater to run five or so minutes that means the thermostat is working. then restart when the temp calls for heat but if the igniter does not work it will not light up again.

The pilot light is ignited by a automatic ignitor. It will need a new replacement to operate the heat to work

Check that the pilot light is lit and flame kicks on when dryer is activated. If no flame, then check gas valve. If only pilot remains lit but does not increase when dryer is activated, then you could have a bad coupler or sensor or circuit problem which would have to be tested with a voltmeter and/or test light.

Dryer does not have pilot light.  There is an ignitor that glows when the dryer is started and lights the flame when the gas begins to flow.  With the front of the dryer off start it up and look for the glow. when it glows hot enough (or on a newer model it might be a spark) the gas should ignite.  When the flame sensor sees that the gas is ignited it shuts off the ignitor and keeps the gas valve open until the temperature sensor gets high and shuts it off.  When the temp sensor cools down the cycle repeats.
If no glow or spark-->bad ignitor If no gas flow-->bad flame sensor or bad gas valve coil If gas comes on and goes off quickly-->lint filter and/or vent pipe or outlet may be clogged or bad flame sensor.

Most new dryers don't actually have pilot lights. They use an electric heater that turns red hot, and ignites the gas at the right time. If your trying to light the pilot light (which probably doesn't exist) because the gas isnt being ignited,,, its possible that the electric igniter needs to be replaced.

should have electronic igniter that light gas after turned on.

That model does not have a pilot light.  It has an electronic ignitor.  If it is not igniting, either the igniter is not getting a signal to ignite, the igniter is burned out, or the gas solenoid is broken.  Probably the igniter is burned out.  It is item number 3018 at RepairClinic.com.