guarantee that your crypto assets, which you transfer to the Wallet are not sold, encumbered, not in contention, or under seizure, and that neither exist any rights of third parties to your crypto assets.
This is one of the Terms of Use "conditions" and has been approved by you, so this "loose" term will make many restrictions can be imposed upon it.
I don't think they are scammers but selective scammers so you have no choice.
Contact support team and after recovering your money stay away from them.