On Monday, January 28, 2013 5:39:26 PM UTC, Rick Hughes wrote:

I have now sent another mail to them mail to them ....

I expect they'll ignore it.
Don't assume they'll act with any integrity, as most traders would; the whole credit not has been carefully designed to trap the unwary customer. You'll have to sue or abandon your money.

The simple fact is that you were unaware of the expiry date since they had not advised you of the T&Cs in tiny print on their credit not. They're trying to impose additional, unfair terms on a done deal.