Mis sold my contract

[Matt19864]

Upgraded my phone in Nov 24, was to send my old handset back and I would get a discount on my line rental. Fast forward 4 months and I had only received my returns parcel to send my old handset set back which I have done, now over the 4 months I had rung customer services a few times to sort the issue each time to be told that it was sorted and I would get my parcel and the discount is applied. Now my handset has been return, I have received no discount on my bills since Nov, spoke to customer services today to be told that I am not entitled to any discount as my contract was took out after the end of August (29th). I feel like this contract was mis sold to me, I have sent a complaints thing online and I am waiting on the call back which can take 7 days. 

[Peter_W]

Hi @Matt19864 .

Thanks for reaching out to us here on The Community!

Have you got any proof mentioning the trade-in discount from when you placed your order, such as a confirmation email?
You've definitely done the right thing in raising this as a complaint, but it'll definitely help our team out if you're able to provide something in writing alongside the query.

They'll be sure to investigate everything showing at our end too.
Peter