Advice on pixmania

I bought a scanner from Pixmania

It arrived without a uk plug so i cant use it. i went out and bought my own
and the scanner is DOA.

I have told pixmania to collect it and refund me but they refused saying i
have to pay the return postage. Estimated at £20

Surely i have a case against them?. i have quoted SOGA etc but there reply
was:


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We kindly inform you that when items are returned under the thirty day
satisfied or money back guarantee, the returns postage is at the customer's
account.

We apologise for the inconvenience and if you have any further questions,
please contact us

Best regards,

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