Political Transaction

This once popped up when I was trying to do an online transaction for a T-Shirt I was trying to buy online. What are the Odds that the letters B J P, gets picked randomly from a set of 16 letters which are there on my ATM - Debit Card. Lets see

1 * 1 * 1 / C(16,3)

which translates to

1 / 560

Or in other words there is a 1 in 560 chance of that happening.

P.S: BJP is the short form of one of the bigger political parties in India.

After entering the correct values I ended up with this.
The followed by this error. Finally after about couple of hours got through the banking site. And I was able to purchase the T-Shirt.