I sent a letter to Midland Credit Management ( MCM ) on XXXX/XXXX/15 via certified mail asking them to stop contacting me via telephone. My letter requested them to validate the amount of the debt, the name of the creditor to whom the debt is owed, a verification or copy of any judgment, and proof that they are licensed to collect debt in the state of Ohio. I had received no prior written communication from this company and asked them to send me details on a debt they say I owe in writing only. The number they are contacting me on is a work phone number that I do not own and I do not use for personal business. Doing so is a violation of the agreement I have with my employer for it use. I received a reply from Midland Credit Management dated XXXX/XXXX/15 stating that they are unable to locate an account in their system for me and that additional information is needed. I was asked to send a Full account number, social security number, address or previous address, full name, and phone number. I could not provide them with an account number as I had received no communication from them with an account number or an original creditor. I also am not willing to provide a social security number to a business that states it has business with me but can not clarify what the business is. My address, phone number, and full name were provided in the letter I sent. Despite MCM claiming to not be able to locate a record for me, the calls did stop for a time. During this time I received no further written communication from MCM with any information regarding the debt they saw I owe. However, during the week of XXXX/XXXX/15, I began to receive several phone calls from an auto dialer sometimes XXXX times in XXXX day. I decided to answer the phone on XXXX/XXXX/15 as I was not aware of who the calls were coming from originally as the number being used during this round of calls is different than what was used previously. The represenative asked for me by name and stated they were with MCM and attempting to collect a debt. This was surprising as I stated before, I requested only written communication and had not received any response to my request for validation/verification. I provided the agent with my cell phone number and informed them I would call them back as soon as I was able. To which the agent responded that if they did not hear from me in 10 minutes they would call me.The agent also claimed that legal action was pending against me. As they called during the business day, I was not able to call them in a timely manner and they have yet to contact me again today.