Lizten very karefully. I zhall zay zis only vonce.

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Next time you make a purchase...  If you sign up to their newsletter, you'll get a free £5 voucher.

Then the next time you make a purchase... If you sign up to their newsletter, you'll get a free £5 voucher.

Ooops, zat iz three times.

I hope that doesn't screw it up for me, I've been doing that for years. 

With any luck, this message will self destruct shortly.