Calls a few times a day and leaves no message..I really wonder how these scammers get our numbers?

I got this call today from this number. I answered and said hello 3 ot 4 times. They never said anything. SO I hung up and they called back. I let it go to my voice mail. They left no message.

got a call today from this number.  Let it go to voice mail.  No message left.  Called back blocking my number a recording said the call would be monitored.  The female answering said, "Pinnacle Financial Group".

I got 2 calls from 313-483-7789 today. One was this morning and the second one was in the afternoon. They say that the call is from a Debt Collector. But the people in the message were very hard to understand. The first one garbled his words so it is next to impossible to make out what he is saying. I only got maybe five words out of 30 to 40. The other person spilled out the 800 number so fast that all I really got was that it is an 800 number that they want you to call back. I don't call people that I don't know and don't have a number for. So they won't be getting any call from me.

I've been getting alot of calls from this number. They leave messages that sound like an automated machine asking for a person I don't know. They are definitely debt collectors.