You need to keep your account secure. And of course make sure you are using 2FA.
If you see trading in your history which were not made by you – please, understand – it’s impossible to do them without knowing your login and password.
No one can do anything about it.
If you see withdrawals which were made not by you – you need to know that it is impossible to do that without having access to e-mail as every Crypto-exchange requires e-mail confirmations for every withdrawal – your e-mail compromised.
Please, note – e-mails can be deleted. But in case there was withdrawals – your Crypto-exchange may have all logs from mailserver for last 24 hours so they can prove they indeed sent confirmation emails.
You need to keep your credentials very safe, also it is very recommended to use 2FA.
All transactions on exchange are final and nothing can be reversed.