I answered. sounded like a speaker phone in a large room. In English, a Foreign-accent voice said they were with some [unclear mortgage company] and wanted to talk to  mister [ my last name].  I did not confirm my name, but they had it right, so they must have access to a list of people exploring new mortgages, or refinancing.

I could not hear them clearly and asked them to take it off the speaker phone so I could hear them better.

They did not, but they "tapped" [clunked] the microphone of whatever they were speaking with and asked me "if that was better."   [" Is this better?"]

it was not, I told them it was not.

They hung up. no click, just dead. I waited.  nothing.  i hung up.

I called 803-274-0618 back.  Message said It was a disconnected number.

Have been receiving calls on my cell phone from this number about 4 times a day for 4 days per week for the past month.  When I call the number back it says it is not in service and when I answer the incoming call it disconnects immediately.