Outstanding Bill on Closed Account

I closed my account with Telus last February over the phone, but apparently there was a balance owed (136.82) that was sent to collections. I received no letters, notification, or emails regarding my outstanding balance prior to Telus sending it to ACRM. I phoned Telus, who confirmed that they have a very old address on file and not the last address I had when I was in service with them (although... I updated my address with them each time we moved). So if there were notifications, it wasn't sent to the address that their service was installed to, which was unfair. They also confirmed they waived $100 due to it being a mistake (They thought I didn't return equipment, but it was returned). TELUS told me my outstanding balance is 25.69 and not 136.83. I phoned customer service billing  to provide an email or printed statement, but they couldn't help out further. ACRM requires this to update the balance they have. How can I get a copy of my outstanding balance on a TELUS account closed 10 months ago?