guarda.coは安全ですか？

I kept BSV for more than a year and now I wanted to exchange it for another currency. Unfortunately, I used the service Guarda.co. With my phrase I opened BSV wallet and exchanged to LTC in their web version. However, you cannot insert your own wallet address - the system inserts the wallet address on its own. Well, I thought that after the exchange I would transfer money to my main wallet. Therefore, I did not betray the significance of this feature, but in vain. After a while, I again logged into my account and saw that the exchange was made, but there was no money. The LTC wallet for which the exchange was made is hidden and is no longer available for me. For a long time I corresponded with support, which told me that if I see the exchange history, I will definitely be able to restore my wallet. But in the end it turned out that I had to save a file on my computer that gives access to the wallet. Where else have you seen such a system where when using the web version you need to download something to your computer? But it turned out that the newly created wallets in their accounts are in no way tied to a phrase, so after a new login all new wallets are lost. That's how I lost more than 1 LTC. I do not recommend Guarda.co.