I didn't answer, & they left no message at all. This call was preceded by 2 other similar calls from different numbers within the last 5 minutes. One was unknown, the other from a known telemarketer number.
I love this website. Finally, we can share our knowledge about these telephone vermin!
Most people only get a limited number of minutes a month on their mobile phones. When a telemarketer calls on a mobile number, it is similar to outright theft.