You are still able to recover your account if you have access to the Steam account attached to the ESEA account and know the email address that is currently attached to the ESEA account.
Visit the account recovery panel and fill out all of the information to begin the account recovery process.
What if my account is currently Premium or Insider?
If your account is currently being paid for through PayPal.com before you lost access to it and you cannot complete the process above, please open a support ticket on a new account to have your problem resolved as soon as possible.
If the account you are trying to obtain access to is no longer being paid for through PayPal.com then we cannot change the information on it to allow you access and your only other option will be to create a new account. You can still follow this process to move your Steam account from your old ESEA account to a new one.