Long story short: It's PNC Bank trying to get money.

It's a computer-generated call to address monies wanted by the bank for whatever reason -- that's individual to each person called.
If the computer does NOT get an answer, it disconnects the call.
If the computer DOES get an answer, it puts the call into a queue to hold for a human representative of the bank.

THEY SAY THEY ARE PNC BANK AND WE DON'T HAVE AN ACCOUNT WITH THEM. THEY CALL 3-4 TIMES A WEEK AND IT'S VERY ANNOYING.

Pnc bank

This number keeps calling.