I cant advise you on how to proceed. You have options, based on the law. They have apparently violated requirements of the FDCPA (discussed below), which can be dealt with in a number of ways.
Administrative enforcement of the FDCPA is charged to the Federal Trade Commission (FTC). So if they have violated any provision of the FDCPA. your adminsittative avenue is to file a complaint with the FTC under FDCPA 814. The FTC has the power to act on your complaint, but from practical eperience, the FTC very rarely will take legal action against the debt collector unless it relates to a big-ticket, joint-action complaint by many creditors. So dont hold your breath on that one.
You can contact your state attorney general, and file a similar complaint under their state version of the FDCPA. Again, they may or may not put it high on their lheir prority list, but also an action you can take.
You can file a complaint with your local BBB, who will write a letter of inquiry, but has no actutal legal standing.
OR, you can just bring legal action on your own,and forgo any decision making by others. But that will cost you time and money. And a showing of the actual amount of monetary harm their violation caused.
As to the substance of their actions, please read FDCPA 804.
What they are entited to do is to call a party other than yourseof, such as your employer, merely to acquire location information on how to contact you. They cannot, in any such communication with a third party, state that you, the consumer, owes a debt. They are limited to only one call to that third party, unless the party has requested that they call again (unlikely), or "the debt collector reasonably believes that the earler response of such person is erroneous or incomplete." Kinda nebulous statutory language. Hard for you to legally enforce a statute based on their "belief.".
You have the right, under FDCPA 805(c), to notify then in writing that they are to cease all further communications with you.
You also have the right, under FDCPA 805(b), to notify them that,except for their entitled, one time call under FDCPA 804(3), limted only to obatinind your location information, that they are to also cease an communicattion with any third party.
You additionally have the right, under FDPA 805(a)(3), to notify them that they are not to make any calls to your place of business, which requires only that you state, in that notification, that your employer prohibits such private communications not related to your job.
