early upgrade - sent old phone via prepaid envelope - EE stating not received

[HVP22]

Hi

I completed an early upgrade; received the prepaid envelope and sent my old phone back.

EE are now saying they have not received it and are wanting to charge me £275.

How can i contest this please?

[Christopher_B]

Hi @HVP22

I hope you're well and having a nice weekend, other than this issue of course. 

Could I please just check when it was you posted the phone? 

Thanks 

Chris