312-800-9007

Call to my cell phone. Does not even ring if you call it back

Got a call from this unknown number to my cell. Wordless voicemail.  Deleted.

"You've won a cruise - press one to connect to our prize agent" for a contest that I never entered. At least they give you an option to "remove from call list" which is what I selected.

Pressing buttons leads to an increase in calls.

Did not answer call; did not leave a voicemail

They never leave a voicemail, can't return call to see what they are or want, phone never rings on call back.  Have received this call a few times, never by company name, just by city - Chicago, IL

Note that by calling back you run the risk of validating your phone number as a "live" number with the scammer. These calls are usually robo-dialed with no guarantee of reaching an active phone number. When you answer and say "Hello," and especially when you call back, your number gets listed as available to scam.

These days it just isn't wise to even answer an unknown number, and much less so to call back.