Received a call from 409-202-3054.
It is my area code.
I picked up and said "Hello".
There was no response.
I stayed online until I received a fast busy tone.
I think this may be the scam where the "phone company" gets paid a small fee for connecting to another phone company's customer.
They do not want to talk to you.
They just want you to answer, stay online long enough for them to register the call.
And then they hang up.
The fee is small, somewhere around half a cent per call or less.
A lot of calls using auto-dialers adds up quickly.

Received a call from 409-202-3054.
I did not answer.
It rang 3 times and then hung up.
They left no message.
See my previous note above.

they keep calling and bugging me for over two weeks.

They left a voicemail 1:20 minutes long. Didn't say anything but there was a lot of background noise like a call center.