about a debt collector

There are a few unanswered details in your question.  Did you close the account more than 5 years ago?  If you did, the claim may be past the Statute of Limitations, so the Bank would have no legal right to sue you for the charges.Do you actually owe the money?  Are the charges correct?  Because if the charges are NOT correct, you should actively dispute and challenge the debt collector to prove the debt.Was this a consumer bank account or a business bank account?  Debt Collection Practices laws apply only to consumer debts.  Commercial debt collectors do not need to comply with these laws.Are you being contacted by the Bank itself, or a collection agency on behalf of the bank?  The Federal Fair Debt Collection Practices Act (FDCPA) only applies to third party collectors such as collection agencies.  However the Florida Consumer Collections Practices Act (FCCPA) can apply to both original creditors and third party collectors.Do you want to stop all contact with the debt collector?  If you do, it may prompt the creditor to sue -- but that may depend on the amount of the debt.  The bigger the debt, the more likely that the creditor will sue.You can write the collection agency a letter, saying (a) you dispute the charges (and why, if your dispute is legitimate), (b) you request "verification of the debt," (c) you demand that they stop all telephone calls and only contact you by mail, or email if you prefer, or not at all.  I recommend that you send the letter by certified mail, and keep a copy with the certified mail receipts.  All that does is prevent them from bothering you.If the debt is legitimate, the bank or debt collector can still put a negative entry on your credit report or sue you to collect the debt, but they should not bother you any more.  If you DO receive further telephone calls or other collection activity, go meet with an attorney who handles FDCPA claims against Creditors.  If the creditor/debt collector has violated the FDCPA or FCCPA, most attorneys will handle the case without costing you attorney's fees, as they will get fees from the other side.