With really no helpful information given, you can try lookup tables (there’s a lot of rainbow table services out there). Some of the common hashes are also found by just brute forcing.
REGISTER or login:
I am not sure that you are aware but you seem to be missing quite a bit out of the question.
Can you add allot more information on what you are trying to do and why? It is not likely that we will help you do something that might not be correct etc.
why do u need to hack your own password when you know your password?