I have the same problem I've contact sonos and there's no more codes available.

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I just went on live chat with Amazon customer service last night, told her I owned 2 Sonos products and was very disappointed that I didn’t receive a discount code. She said there had been a technical problem with sending out the codes - told me to place an order for the Dot and she took £25 off there and then! Fantastic service from Amazon and looking forward to trying it out tonight 🙂

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