I missed the call. They left no message.

Called a small business multiple times (usually 2-3 times a day) for several days in a row.  No matter what time of day, we always answer the phone the same - this call starts off with a loud, fax-like beep WHILE we are in the middle of answering the phone (thank you for calling *blah blah*, how can we help, etc).
When I am dealing with what I think are automated systems I rarely, if ever, say 'Hello' because I know that is a trigger word for robocaller systems.
This morning the pattern of behavior changed - the loud fax-like beep interrupted the phone greeting/answering (again) and I stopped talking and waited for something to happen.
Then, some weird recording came on the line and said: "We're sorry.  We will remove you from our list as it is obvious you are not interested in this opportunity."
...???

I have no idea - my recommendation is to ignore them until they go away, lol

I called back this number and it was a automated voice mestage saying I won something. Sounds suspicious.

I missed a call. they left no message. I tried calling back and was met with "Verizon wireless. The wireless customer you are calling is not available at this time."

They called me twice. The first time I didn't pick up because I didn't know who it was but then the following day I answered I heard a loud beep and the they hung up I keep trying to call them back but there's no dialer tone it just hangs up right before the dialer tone would usually happen.
Is there any insight to who these people/robots are?