As a follow-up (just maybe to help you see around some corners), the only way they will be able to come against you personally is under something called the alter ego theory,
The case they MAY try to make is that you "pierced your corporate veil."
Corporations exist in part to shield the personal assets
from personal liability for the debts or actions of a corporation. Unlike a general partnership
or sole proprietorship in which the owner could be held responsible for all the debts of the company, a corporation traditionally limited the personal liability of the shareholders.
And one of the reasons that the LLC is the fastest growing entity type out there, is that it has the flexibility of a partnership but the liability protection of a corporation.
What they, again MAY try to argue is that the LLC was merely a formality and that the LLC neglected the formalities and protocols that sustain the treatment of the LLC as a separate entity. ... that there was enough co-mingling of personal and business assets, for example, that the LLC was just an "alter ego" of you.
Your first response should be, not this was an LLC, these are not my personal debts.
THen the burden
of proof will be on them that you somehow created this LLC as a sham, rather than to conduct a business.
RIGHT NOW? ... they're just trying to scare you into paying.
If you had a valid LLC, your are not personally responsible.
Hope this helps