If you have new or further relevant evidence that supports your case you can file a Supplemental Claim. You can also appeal to the U.S. Court of Appeals for Veterans Claims.
There is something else about the waiting process for approval.  If the VA schedules any kind of exam for me, is it required that I attend it?
Yes, please be sure not to miss it.
I have requested an appeal but I cannot continue on my own, where can I get help to continue with the process?