Constant unwanted calls!

This company has been calling me constantly for almost the past week, whether it be in the morning or late at night (after normal business hours) I usually don't pick up unknown numbers but I kept receiving calls from them (using three different numbers) here is the log below:
July 26 2:03pm
July 27 1:24pm
July 27 3:40pm
July 27 5:48pm
July 30 9:43am
July 30 2:35pm
July 31 9:13am
July 31 11:32am
July 31 1:54pm
July 31 4:21pm
July 31 5:42pm
July 31 7:29pm
Aug 1 9:52am