A teeny-tiny decimal point is quite a powerful thing, not to be overlooked. Unfortunately, if you don’t pay attention to it, you could end up paying way more than you planned to, like one consumer did when paying for a ride to an airport.

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Mary Morehead of Seattle was in California for a wedding and took a shuttle from the Long Beach Airport to Los Angeles International Airport after returning her rental car. The ride cost $46 including tip, and when she signed the credit card receipt, she saw it said $4600, KOMO reported.

Morehead signed it. She thought the small receipt was formatted to omit the decimal point.

The next month, she saw the $4,600 charge on her credit card statement and called her issuer to dispute the charge. They issued Morehead a credit but later called her to say the driver presented the receipt for $4,600, so she would be charged in a later bill. If she wanted her money back, it was up to her to find it.

It took Morehead many months and several phone calls to resolve the problem, according to KOMO.

She tracked down the driver’s phone number in early December, and when she called him, he said he didn’t know the total had been entered incorrectly. The driver wired Morehead $4,600 on Dec. 7, about five months after she took the shuttle.

Not only is Morehead’s experience a lesson to look closely at a receipts, it also shows the importance of reviewing account activity.

Don't have to wait for your monthly credit card statement to arrive in order to review your purchases, and the sooner you spot an error, the more quickly you're likely to resolve it. The longer it goes unnoticed, the more likely fraudulent activity or incorrect information could be reported to the major credit reporting agencies, which can damage your credit score until you get the errors fixed.