Product: Debt collection

I believe this company had contacted me previously at this place of business. I kept receiving calls from XXXX but, I did not keep track at the time. I finally got in touch with someone at the agency and they assured me they would remove our office phone number as the employee they were looking for is a field employee regarding a previous occurrence with the same phone #. At that point they were put on notice this was a business and an incorrect phone number to reach anyone regarding debt and I had figured we would not continue to get any calls from them. 
I got a call today at XXXX at XXXX from XXXX, I answered and I identified our business name, I was then hung up on immediately after. I called the number back and indicated to the representative the number again was likely incorrect, the name she gave was " XXXX XXXX '' a female. I indicated I had already put them on notice so I would like to know who they were calling for so I could ensure we do not continue to receive the same calls and verify if they had already called for this person after I told them this is the wrong number and to not call here. She told me there was no way they could have called me because they just got the account. I indicated I was calling off of the caller ID phone number so YES they did call our business, red flag # 1. I then asked who they were calling for again so I could confirm if they put the " wrong number '' update on all their files after they are told previously ( maybe a different debtor ). The representative refused to give me the name of who they were calling for, which is a no no, they are required to inform you who they are where they are calling from and who they are calling for. I then remembered they did this to me on the previous call I made to them about an incorrect phone number and I talked to a manager then and again, I asked for her manager directly at this time as well ( I did collections for 13 years, I am aware what they are doing is illegal ), a person got on the line and I could not confirm if they were female or male, they indicated their name was " XXXX XXXX '' they stated they were a manager only after I asked if he was a manageXXXX or not. I then again explained I have already put them on notice indicating this is an invalid number for collection purposes and wanted to know the name of the person of whom they are calling our business for, the manager XXXX XXXX then advised me that he can not disclose that information to me, I know this to be false they can and they are supposed to. He then started to talk over me and cut me off, I asked what the name of the company was, he told me " XXXX '' I repeated " XXXX ''? then asked why it comes up as XXXX XXXX XXXX XXXX on my caller ID? He refused to answer that question as well and told me that he already addressed my concerns and there was nothing else he could do for me. Again speaking over me and being less than professional. I then advised him I wanted to know the name of the person they are calling for, as I believe I had already notified them they can not reach that person here, he continued to go back and forth with me indicating no fault and being very rude and belittling, he did not help me one bit nor did they address the incorrect phone number concern. I had to call back and pretend I was a customer to get the mailing address to file the complaint as that information was not provided to me either.