Complaints about Phone Numbers833-541-####

Received a multiple calls on weekends and holidays from (833)541-4221. My Phone registered the number as spam and sent it to voice-mail. An automated message stated they were a medical billing department and to call back. But no answer when I return the calls.

This is why I'm calling from Chase Bank your dedicated account specialist please return my call at 866-335-9405 extension 105-002-7128!!!!??? Who has a 10 digit extension number!!!!??