Whoever this is, they need to quit. They are calling and hanging up and calling with a blocked number. If you want to talk to me, say something and don't block your number. My phone will no longer accept calls from blocked numbers.

This company or person has a block number when you try to call back.  They call at various hours all day long.

I'm getting hang-up calls from this number despite being on the do-not-call list.

I called back.  They asked if it is a personal call or business call.  I selected business and got transferred.  They finally answered and said the are a collection service and wanted to know if they could provide some services for me.