You can create a thread in Meta to claim your old account, usually it will get the attention/response of the admin faster. And some methods (my suggestion) to prove ownership of your old account are:
1. Write the name "smartcontracts100" somewhere (maybe on the profile page) in your old portfolio. This is based on your
post history which seems to link the same portfolio address.
2. You have sent BTC based on
this post (even if you have problems afterwards). If you can sign a message from the sender's address in this
txid, I think that will also help.
Hopefully this method can be considered by the admin to get your old account.
Good luck