How do I cancel a started return?

[artcreater-2009]

Bought a top I needed to return. Messaged the seller etc, went off to the post office and posted it and obtained tracking info. Came home and to upload the tracking details I thought I'd start a return. My problem is that Ebay has emailed me a postage label and automatically added a different tracking number. I don't need this as I've already posted the item back to the seller. Does anyone know if I can cancel this postage label and not get charged for it? I have since messaged the seller again and told her my tracking number as I don't see any way of amending it on the started return. I've  tried the faqs but it doesn't tell me anything useful.

Thanks for any help.

[john1297576]

You don't say why you were returning, but if seller provided a return label that implies "Not as Described".

You should have read the instructions, once you have paid that is it, the seller did it properly, they will not pay the postage now.

[artcreater-2009]

Sorry, should have said. The top just didn't fit properly and after messaging the seller they said it was fine and gave me their return address to send it back. Hadn't started a return at that point. Went off and posted it then got back home wanting to upload the tracking info I'd just obtained but when I started the returns process I didn't realise ebay would email me a postage label and a different tracking number! Now I'm being asked to post by the 13th August but of course it's already posted. I'd like to know if I can somehow cancel the label and upload my tracking number so ebay can see I've posted the top back or is it not possible?