Who called from 4848911779

Called on my cell. No message Left

same must be a robo call

Called my DNC registered landline. Two calls back to back. No voicemail. The Whitepages didn't find a matching number. All signs of a telemarketer.

Calls land line every few days.  Hangs up without leaving message.

Report the number to the FBI. It's THEIR problem:

https://tips.fbi.gov/