I was trying to buy something online and was gonna use my bank account option to pay for it, instead of my credit card option, and I noticed it wasn't there. I saw that if you have a failed transaction it removes the bank account, and sure enough I check my email and there was one saying one failed so it was removed. But I have a couple of questions. 1. Why did it fail if I had more than enough money to pay for it? 2. How do I get it back and prevent this from happening again? The email says to confirm with my bank to make sure its right, but I don't know what it means by saying confirm with your bank, and I don't know where to go from there.