Who called from 2534141298

Calls all the time. Does not leave any message.

will not tell who they really are. never stop calling

Probably time to obtain a call blocker device, app, or phone.
Google "call blocker" to see the various types, and find one that best meets your needs.

Refuses to tell me what kind of company they are. Keeps saying it's personal and confidential.

Called at 4:15PM Caller ID shows UNKNOWN NAME.  I answered and they asked for someone with my last name and a first name that I do not recognize.  I told them I never heard of the person.  I called their number back and get a recording of the company name that is hard to understand that says "this is a recorded line"  I then hung up.