If you've checked everything else, it could still be one of three things:
1. The element may need to be changed. It's a simple and straight forward fix and with help from the internet, anyone can do this repair fairly easily.
2. The are a couple of fuses that are located on the outside of the element housing. When I changed the element on our dryer I replaced these as well. Again, this is an easy install.
3. There is another breaker that is located just inside the front cover. This was not the problem with our dryer but I've heard that it is a common problem. Easy fix - found the instructions by using Google search.
Hope this helps.