Trade in

[Shs74]

I upgraded to iPhone 13pro max when it was released back in September. I selected my plan and done the trade in my old handset for 15% discount each month. However as many may well remember the 13pro max took months to get delivered from the release date meaning I didn’t send my old handset back in the states time frame. Once I reviewed new phone I sent my old one next day but to this day I’m still paying full contract price £71 when contract agreement is £55 also I never received any confirmation on ee receiving my old phone. 
Can anyone can help solve this and I feel I’m due a refund for each months payment I haven’t had the discount 

thanks 

[Chris_B]

@Shs74  you will have to call customer services about this.   Did you also receive confirmation that they receive the phone ? 

[Shs74]

No I haven’t received any confirmation that they received my old handset. 

[Chris_B]

@Shs74  You did use the returns package that was sent to you ?