If you face one of these scary situations, use our tricks to protect your pocketbook. By Stacy Rapacon, Online Editor October 1, 2009 A phantom charge haunts your bill. In July, technical difficulties struck about 13,000 Visa cardholders, who were each charged more than $23 quadrillion for such mundane purchases as gas and cigarettes. (They were dinged by overdraft fees, too.) Solution: Once the customers noticed the 17-figure mistakes, their banks and Visa quickly removed the charges, along with the fees they triggered. It should be just as easy a fix for you, if faced with a similar situation: Contact your card issuer and question an unfamiliar charge. If you can’t solve the problem over the phone, you may have to resort to a formal dispute with your card issuer, in writing, within 60 days. Send your complaint via certified mail to the address for billing inquiries -- not the one for payments -- and include your name, account number, address, an explanation of the error, plus copies of the bill, receipts and any other supporting documents. The lender must acknowledge your complaint within 30 days, remove the charge until the issue is resolved, and clear up the dispute within two billing cycles or 90 days. Your wallet has mysteriously disappeared. In the hollow of a dead Central Park cherry tree, a wallet that went missing 27 years ago reappeared in early July, minus just $20. But most pickpocket victims aren’t even that lucky. More often than not, their wallets and the contents vanish. Solution: After you report your stolen wallet to the police, your bank and your credit-card companies, ask one of the three credit bureaus -- Equifax, Experian or TransUnion -- to place a fraud alert on your account (the bureau you contact will notify the other two). The alert lasts 90 days and gets you a free credit report from each agency so you can monitor whether the perp is also trying to masquerade as you. With a police report, you can extend the alert up to seven years and get two free reports from each bureau annually. Also, be sure your bank and credit-card companies issue new cards and account numbers. But kiss your cash goodbye. Advertisement Your credit score is falling. The credit-card delinquency rate hit a record 6.5% in the first quarter of 2009, up from 4.8% a year earlier, and banks are cutting credit limits. So many consumers may be feeling the pinch. Solution: Paying off your balance in full will boost your score. If that’s not possible, at least make the minimum payment on time. Other ways to increase your score: Use your cards regularly, limit your balance to a maximum of 30% of your available credit, make charges occasionally on inactive accounts so that those accounts stay open, and don’t apply for unnecessary new credit. The tax boogeyman marks your return for an audit. Before you duck under the covers, you should know that only one in 100 tax returns is audited, and few filers wind up face-to-face with the dreaded tax man. Most audits are handled by mail. Solution: You have no better weapon to battle the beast than complete, accurate and organized records. Review your return, matching all the numbers to the appropriate receipt or statement, and be ready to explain anything on it. Be honest, but keep your explanations brief and on point. You could enlist backup from a pro, who may even go to the audit in your place. If something is amiss, you’ll have to pay the extra taxes plus interest. If you deserve a refund, you’ll also get interest. If you disagree with the auditor’s findings, you can appeal and request to meet with a supervisor.