I opened my account with 6 lines on april 10, 2018 and closed all line very next day within 24 hours due to network service issues at my home and retail store manager had refunded me all activation fees also since It was cancelled within 24 hours and closed my account with zero balanced. I started receiving call from collection agency on June 2018 that I owed $300 to T-mobile. I went to retail store very next day and Store manager had called customer care department and Customer Care Representative had assured me that I will receive zero balance revised bill and they will resolve also with collection agency that way It will not affect my credit report. After month I had received call again from collection agency for $400.59 balance. I called again and Customer care rep again assured me that I will receive final bill on my email with zero balanced in 24-48 hours but never got any email till today. Retail store manager had printed me all memos that was written by all representative on my account and also print me receipt that shows that account was cancelled with in 24 hours and since all receipt have my personal informations so I don't want to post it here.I had not used account and cancelled on same day I have to deal with this collection agency everyday and It will affect so badly on my credit report. I have all proof from retail store that confirm that account was cancelled and I feel like I am being tortured without any reason and due to not any synchronization of retail store system with billing department also. I have no charge and bills to pay. can someone please help me stop this?