Question on amount wrongfully sent to collections

I cancelled my internet services with Telus last year, and I called them earlier this year for copies of my invoices for tax season since they deleted all of my invoices from my online account when I cancelled with them. The agent had informed me that they normally charge a fee but would waive it for me. I informed them that I did not want the invoices if I was going to be charged. The agent assured me I wasn't going to be charged. Fast forward to this week, I receive an email from  General Credit Services Inc. saying I had a balance owing for Telus Home Services. I go on Telus chat this time to inquire about any balances owing and the amount was a fee for the copies of the invoices. Telus informed me they have now waived the fee. I asked for them to also update the collection agency but they said it was never sent to collections, however I literally have an email from the collection agency. I'm wondering what my next steps should be. I shouldn't be having to pay a fee to the collection agency for something I was promised I wouldn't be charged for, and I don't want them to harrass me, and I'm worried about this showing up on my credit report negatively. Is there any way to contact a certain Telus division for them to discuss this with the Collection  Agency?