Enforcement of lien

Assuming your company filed the lien, you'll need an attorney to commence a foreclosure action in court, because corporate entities cannot appear in court without counsel. Also, from a practical perspective, lien foreclosure litigation is very technical, so working with counsel is preferable in any event.

Greetings. It appears you would like to know whether you can proceed pro se with a lien you had filed. Proceeding pro se in a lien matter, indeed any matter, is not recommended. As one authority has said, lien foreclosure trials are "like any other trial: the same rules regarding discovery and evidence apply; there are pretrial, trial, and post trial motions, interim hearings, testimony, and findings and judgments. Each party has to prove the allegations that make that party's cause of action, affirmative defense, crossclaim, or counterclaim." (Biser Rubin Brown) As you can tell from this paragraph, there may be much to lien litigation. It is therefore better to hire a good New York lawyer instead of trying to do it alone. 

If the Lien is in the name of a corporation, you must have an attorney, corporations may only appear in court in New York by counsel. Moreover, lien foreclosures are highly technical proceedings and you may need an attorney to assist you with the proceeding. You may want to consider retaiing someone with experience in lien foreclosures. Best of luck!