Who called from 2102020575

this is a collection agency known for using scare tactics / terrorism to provoke a response from you. do not answer calls from this number or respond to them in any way. block, delete, move along. nothing to see here, folks.

It would have  been a lot more helpful to know the name of this debt collector and anything else you know about them.

I got a threat from this phone number. Said over check and go. That was paid 2 years ago

Well without more information this is the best advice i can give you:

Read up on your rights here, get template letters to send and also make a complaint at this government site: http://www.consumerfinance.gov/

Also file a complaint with your State Attorney General's office.
List of State AG’s offices:  http://consumerfraudreporting.org/stateattorneygenerallist.php