I am not familiar with the platform you refer to but it certainly is unfortunate and one of the main reasons why we do not support third party services. There is a set system in place to help recover stolen funds and proof of ownership of the affected wallet is vitally important. It is not that is was 'allowed' as you stated, moreso the fact that without being able to prove you are the owner of the address in question then an unscrupulous person could attempt to have any wallet frozen for a number of reasons.