Once you enabled the 2FA, whenever you try to log in, the website is going to ask you to inform that code.
For that, you must check your app, where you made the authentication, as the generated code changes frequently.
Every time you log in, you must check your app for the new code generated by the app. In case you already tried the code, and it didn't work, please allow few seconds for your app to change to a new code and try logging in again. Besides, try not to use autofill apps, as if it fills a wrong data, your code will not work. Alternatively, if you do, make sure the information is correct before proceeding.
In case you can't access your account after checking any possible methods, you can request the 2FA deactivation to our support team.