Do you use any third part service which uses your API from Kraken?
you probably need to look for the culprit from there. Using API from exchange on unreliable trading bot can result in trading on some overpriced shitcoin, all you said that happened looks like such a scenario to me.
Thanks, since months I don't use any trading bot at all. And all these stupid trades were done in 1 day, which reduced my fund to be 15% of before.
And until now I cannot login yet to Kraken to check.
And Kraken has not answered me what has happened
If you didn't use the API to any 3rd party software it's impossible that someone can access your Kraken with 2fa and a good password. Unless if someone use your laptop where your 2fa software installed.
Did you login your Kraken account to other devices? Maybe you forgot to logout your Kraken account there and someone use the device and trades your balance accidentally?
Do some check first and maybe someone used your Kraken account maybe your child or your wife or a friend.