They just want to get attention Smile
For me the bitcoin would be the first cryptocurrency in the world. Look at the value, no one can beat bitcoin.

goog

If you have a clue as to what it is then refer it to a professional like Dave at wallet recovery services, but they can only work on it if you give them some ideas to work with from likely choices of password or half remembered ones. If you literally have no idea of a single character then it's toast.