SJM MARKETING ALEX GREEN threating phone calls Internet

These people have been calling my place of employment my house and now they are contacting my family saying that i owe 1150.00 and if i do not pay they can come to my place of employment and take me to jail. I have never had a loan with this company and i even had my bank sent me a detailed list of all my deposits and withdraws from my debit card and there is nothing with that amount nor this company. Since they started calling i had to have my phone number changed i moved but they still keep calling my employment and i'm in fear of losing my job. I can not do this because i have a daughter in college and i have a school loan to pay. These people leave a phone number but when i call back it is no longer in service i even had my local police look into it but they came up with nothing. These people say i can go to jail and if i don't comply i live is in danger and god will be the only one to help you. They even starting calling my family and my parents are now afraid and they are say that their lives are in danger. I wish somthing could be done i'm afraid to answer the phones at work and afraid for my parents.