Dashboard → Security. It takes about a minute and blocks the most common way accounts are lost.
Open Dashboard → Security and enable two-factor authentication. From then on, signing
in asks for a one-time code as well as your password.
We strongly recommend it for any account that can see invoices, licence keys or
project material.
If you lose access to your second factor, raise a support request from an email
address already on the account. We will verify who you are before turning it off —
which is slower than it sounds, and deliberately so.