The money deducted for your 401k and the HSA flex spending account is *your* money, not the employer's--they are acting in a fiduciary capacity to administrate it, but have no claim to the money. Therefore, if it is being misapplied or misappropriated in any way, you would have a cause of action against them. If they are acting carelessly, your claim is based in negligence; if they are acting deliberately, they are committig an intentional wrong. In either event, you could sue them to get the money to which you are entitled; to recover any other losses or cost you incur; and/or for a court order directing them to handle the funds properly.