these guys will call claiming you owe a debt to US cash advance (which you dont)
They hacked some online loan or payday loan site and stole the info that people put up to check on getting a loan with a legit loan company.

they are obviously not americans and claim to be lawyers who have a case and are ready to sue you for the $300 you supposedly owe, which is not over a thousand with fees added.

do not give them any info, just tell them to sue you, better yet use your choice of words for them.
use a whistle or better yet an air horn , kinda gets their attention.

after you tell them over and over again you are a scammer and a bad one they will still call and tell you they will cause your life to end as you know it. promise they are sending the cops to arrest you and put you underneath the jail. i told them go ahead i am writing your number down and i'll give it to the cops when they get here.

i had one last week demand that i let him talk to my manager, yeah right, he said i have to, said who,
this guy who is probably thousands of miles away.
they will threaten your boss, your coworkers, your family, hoping someone is stupid enough to give in.
((you will have to tell your boss what is happening so they will know why you are getting all these calls and giving the idiot on the other end hell each time))
one of my coworkers got involved and he speaks another language so we forward all the calls to him, talk about a hoot.

tell them you are recording the conversation to give it to the FBI.

Anyway don't be afraid just either ignore them and hang up on them or take your days frustrations out on them.
They use many numbers so keep track( i have them listed on a pad )each time tell them the numbers since your have one or two of mine here are some of yours, all of which i have turned over to local authorities and the FBI and whoever else will take them.

if they call one more time i will start giving their number to other telemarketers let them talk to each other.