A debt collection agency is harassing me and my employer on behalf of the bank. Is this legal?

Hi,

I would like to ask if a finance company can file a civil case with the amount of less than AED 5000.

Does a third party have the right to collect the money under another finance company even though the company has been closed and harass anyone even if the employer has no responsibility to them?

Please advise because a lot of people are suffering mentally and psychologically due to their misbehavior and wrongdoings.

Thank you