TYS review: I would like help resolving this issue.

TYS is a credit card payment processing company. I have a one person business and use square to process my customer credit cards. A vendor came into the shop I work in and told me he could get me a much better deal than square. This was in September of 2021. He took all of my banking information.The next day he brought in a small device similar to the square that I use. It would not work. The next week he ordered a larger machine and began having heated conversations with foreigners over the phone. This machine wouldn’t work either. Since September 2021 , I have not used these devices as they would not work. I have called this agent & requested my account be closed . He has not done so. I have repeatedly called, texted, sent letters to the company and they continue to send delinquent account balances upping it into the hundreds each month. I have had to close my business account. This situation has caused me great concern because of the information the company has and their refusal to close my account.