This number called saying that they were a air quality service and wanted to come out and clean out our air ducts. They said they had done work for us in the past, and wanted to come back and do it again with a special promotional offer. I said I wasn't interested and asked him to put me on the do not call list. His response was nope. he repeated that over and over. I said, excuse me? He then said, you heard me, you know what that means. He then hung up on me. Wow...