Called 3 times within 2 hrs. I did not pick up

Called every hour all day for two days.   No message.      I won't answer number I dont know

Claiming to be a mediator for debt collection! Their trying to collect over 1000 for a credit card that I never had from back in 2000 and threaten to file charges against me....  but didn't have my correct address or anything! Any advise on how to handle this would be appreciated!!!! Thanks in advanced....

Called the store I work at saying they had "unfavorable" information on my boss.