Calls are from a landline, under the management of Level 3 Communications, LLC, Los Angeles, CA. Again, this is one of many telemarketers, working under a variety of area codes (213, 310, etc), in that region.
They'll haunt you by phone, in the hopes you call them back. When you contact them, they'll give you the pitch for some NON-TAX DEDUCTIBLE "charitable" organization. Your calling them also allows them to runaround the DO NOT CALL LAWS enacted by the federal government and many states.
Ignore them or report them thru one of these complaint centers. They're a pita, but usually not a police matter. But, DO NOT agree to patronize and donate money to any of the groups they're soliciting for. You open the door to even more harrassment.