Hi I downgraded to BT essentials in November and was asked to return my Wi-Fi disc which I did via Royal Mail within the time limit . However I’m being charged 30 when the post office said it went to yours and was delivered . Now I didn’t get a receipt because the office I used only scan the item how do I get the tracking info so I can check it was sent please do I phone the post office hotline ? Thanks as this 30 pound charge is a lot and I simply cannot afford it . Thanking you in advance .