An HOA lien can be filed without the HOA (or their counsel) having filed a suit. The service comes prior to the filing of the lien when they issue a "Notice of Intent to Create Lien". The HOA must follow a very strict procedural script and service at some point is this process is a key part of that. After that, almost any lienholder can force the sale of a house, its just whether that is in their best interest.
Unfortuneately, there are not enough facts to know where you are in the process or to determine whether you would be better off trying to satisfy the lien or retaining counsel to dispute the process.
The HOA can file a lien and can also take other action to collect on that lien. I would advise entering into a settlement agreement with them if the back fees are really owed, but there is no reason to give them bank account information. If you need further assistance, please contact me.
Mark L. Rosenberg is an attorney admitted to practice in the State of Maryland and the District of Columbia only. This answer is meant to be for educational purposes and no attorney/client relationship is intended or created by this answer. You should consult an attorney in your jurisdiction for information on your case or claim.