Thank you for being an advocate.
Let's call this what it really is, it is harassment and it should be a violation of italki's policy of fair and respectful learning. We should bring this up as a formal complaint. Also, this is a big deal and should not be ignored. Your feelings are valid and should not be swept under the rug. I'm not sure if others know that the are legal violations and can be taken very seriously by police and judiciary branches of law.