Learn how your appliance is supposed to operate so you can determine if it is malfunctioning.
If the dryer is not heating and there is definitely 240 volts getting to the appliance wall outlet, there may be a problem in the appliance's wiring. A common area for that is the main terminal block where the appliance's cord connects to the dryer's wiring.
The main terminal block is usually mounted on the rear of the dryer. Check it and the connecting wiring's appearance. A problem there will usually be visible as a broken wire with possible melted insulation and discoloration of the wiring and terminal connections.
The actual design of the terminal block used on your appliance will vary depending on appliance age and appliance design. They all serve the same purpose.
All of the information in these Appliance Clinic procedures is provided FREE OF CHARGE. No liability is assumed by the author for the accuracy of the contents or damages caused by the use of these procedures.