Exness accounts remain active as long as they are not terminated (either upon request, or by decision of the company). A notice of termination is always sent to your Exness account registered email address, so a good first step is to check your email for such a notice.
If you remember your old Exness account password +
If your Exness account is active, you will be logged in. If your Exness account is inactive, an error message will say “No such login or password. Please check for correctness and try again.”
If you don’t remember your Exness account password +
Follow the link to reset your password, and enter your registered email address. If you see an error saying “Incorrect email” then that Exness account is inactive.