Left no msg. Another website showed several complaints today.

Called again 4 hours later.

This number has called five times today. Not one message left.

After getting multiple calls from this number, I called them back. She was very hesitant to tell me who they were, but said they were calling to book reservations for some kind of resort. I asked politely to be taken off their list, but I doubt that will happen.

You committed Basic Mistake No.3: You called them back. Calling any unknown number is so unwise these days because doing so can result in any number of regrettable outcomes. One being that you've just cemented your number with a scammer as one that reaches a curious (i.e., possibly gullible) Phish who can be scammed. Another unwanted outcome of calling unknown numbers is that you can see an unexpected fraudulent charge on your next phone bill, if you even notice it. Resist the temptation to 1) Answer unknown numbers, 2) To talk to the caller if for some reason you do answer and 3) To call back.