This is an old account I have on the 3D Warehouse, but I don’t remember with what log in. When I sign out with my new account and try to log in again, it just automatically log in with my new account.
I would be happy to help. The best place for requests like this is our Technical Support form.
Please fill out that form with information about your old account, new account, emails that it could be under and we will see what we can do to help you out.