If you have not already replaced the temp selector switch, do so part # 33001656
It tells the bias thermostat when to turn off.
If you still have trouble, replace the dryness control in the console. This the lit panel that shows the dryness.
The part number is 33002389
Both part simply snap into place in the control panel.
Also check your vent to see if it is restricted. Maytag dryers, particularly the Neptunes, must not have foil duct to the wall. The best test for the dryer is to remove the exhaust and place a temperature probe in the air outlet to monitor the dryer as it runs. High heat should be around 155, the delicate setting around 140. If the dryer runs at these temps with no vent attached, suspect a restriction in the duct run.