Have received 2 calls within 3 hours. Let VM pick it up and they just stayed on the line using all of my VM so no one could leave a msg. Lots of scammers have been doing this!!!!
A call blocker can keep that from happening because it answers and hangs up, preventing the call from going to VM.
If your number is a landline, you can use an answering machine by turning off voicemail, and thus have far more "time" for messages. Also an answering machine can allow you to screen calls when you are present to hear them.