A muffin? No, nuffin!

I got a quick email,
I've won a nice prize.
A £10 spend at Starbucks!
What a lovely surprise.

I fancy a coffee,
And something to eat,
A nice chocolate cake,
Would be such a treat.

But oh woe and alas,
Another mail here,
We've made a mistake,
You'll get nothing, we fear!

So now my dear friends,
I'm feeling quite sad,
Cos instead of my muffin,
They've said I'll get...........
Nuffin!