ERC Debt Collection Complaint

ERC Debt collection department,

Other (i.e. phone, health club, etc.) Cont'd attempts collect debt not owed Debt was paid Pennsylvania

a few years ago i have - mobile phone service after few months i transfer my service too - i talk with sprint on that time and they send me return kit for phone the phone i got from - and after that i send that phone back to - i also send them prepaid - card that i got from - because - want me too pay my bill too -. now i got this bill from - and i do not owe this money i talk with them and they said u have too pay otherwise this money goona stay on your credit report and they already did that please help me thanks