These people call numerous times a day and never talk nor leave a message. Here are some of the numbers they use.
302-411-1212
302-411-1023
302-411-5460
302-411-3322
302-411-3838
302-411-1452
302-411-1122
302-411-4111
302-411-6489
302-411-0306
302-411-6485
302-411-5846
I get the same, 17 numbers so far, it must be on a rotary dial.
I believe it's a computer trying to get access to your computer through your smart phone.