Hello from Russia!
We are have permanent problems with resolve cyrillic symbols in usernames, who send request by email. For example, name "Польский Артем" look like "=?UTF-8?B?0J/QvtC70YzRgdC60LjQuSDQkNGA0YLQtdC8?=" - see attach. I think this applies to the Chinese symbols, and others.
Please, check it and resolve.
If possible, repair the incorrect names in the database as well. If this field contains "=? UTF-8" means you can it change! I do not want to do it manually.
Thank you for sharing this feedback.
We have created a Support ticket for this #763356, hope you might have received the notification.
We have informed the concerned team and looking into this, will keep you posted as we progress on this.
Feel free to get back to us for further support.