I found myself in a similar situation. HTX/Huobi blocked the withdrawal of funds and is asking for data that I do not have. In response to all my attempts to clarify the situation, they send me a letter with similar demands. The transfer they had questions about was $250, but they blocked all assets in the account.

On the site HTX.com I did't find the legal name of the company and the place of registration. Maybe someone knows?