Sounds like it could be an issue with the thermostat or a fuse. Even though the element's been replaced, if the thermostat isn’t working properly, it won’t signal the element to heat. Check the wiring to the element too, just in case there’s a loose connection or a short somewhere.
If everything there looks good, you might want to test the control board itself—sometimes the panel works, but the relay or internal circuit controlling the heat can fail. A multimeter will be your best friend for diagnosing. Worst case, you might have to replace the control board.