If your credit card was decliened it can be
for any of the following reasons:
1) There is some kind of a fraud hold on the card. This happens sometimes when the credit card company sees a transaction they don't believe fits your normal buying pattern and they are worried that it might be fraud.
2) There is some other type of problem with the credit card account, for example a restriction placed on it by the credit card company that it may not be used outside your country, or insufficient funds available.
With 1 or 2, you will probably need to call your credit card company and ask them why the charge was declined and to authorize the charge.
3) You typed a number wrong.
4) You chose an incorrect expiration date.
With 3, or 4, you can try to submit the order again.
We look forward to welcoming you as a new student of The Piano Encyclopedia!