When I placed an order on Amazon recently, I was taught a very important lesson about how they process your orders.

I made a rather large purchase on Amazon, as opposed to the $10 to $40 purchases I usually make. This one was over $1000, and I put it on the credit card that I have with the lowest interest rate. My plan was to pay it off in two to three months and end up paying the least amount of interest possible, but that's not what ended up happening.

My credit card company declined the purchase, flagging it as suspicious. I don't blame them. I had recently gotten the balance on that card down to $0, and now suddenly there was a charge of over $1000 on it from Amazon. That would be a red flag for me too, but the thought never crossed my mind when I placed my order.

I got a text message from the credit card company that my payment was declined because of suspicious activity, and asked me to verify it. However, I didn't get the message until an hour after it was sent.

In the meantime, Amazon, seeing that the payment was declined, went ahead and charged the purchase to another credit card of mine they had on file. One with a higher interest rate and higher balance. That's not at all what I wanted or expected. I wanted it on the card that was going to cost me the least in interest, and not jack my balance up higher than I wanted. That's the one that had the zero balance.

I'll admit, life events recently made me have to put more on the credit cards than I wanted to, but with one that was paid off, I thought this was the best way to get the big-ticket stuff I needed without paying more in interest than I had to.

Why did this happen? Here's the explanation from Amazon:

Backup payment methods helps us deliver your shipments and services on time. If there is a problem with your payment, we will automatically charge a backup from your Amazon Wallet for eligible products and services.

Thing is, this wasn't a problem that was my fault. It was just my credit card company trying to protect me and them from fraud. Lesson learned.

If you have more than one payment method registered with Amazon, and don't want them to charge another card if your chosen method of payment runs into problems, here's how to turn it off:

Log on to your Amazon account and go to "Your Account" in the upper right under your name on desktop or the three lines on the left on mobile. Then follow the menu choices in this order:

Your Payments > Settings > Manage Backup Payment Method

You'll see something similar to this on your screen.

Backup Payment Methods

Tap the switch to turn off backup payments. That way if this ever happens to you, your shipment will just be delayed rather than charged to a card you don't want to use.

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