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You've missed credit card payments
This is an obvious one, but if you've been too busy to realize you've fallen behind on payments, you must get caught up before your card will work again. The number of cycles you can go past due before your issuer shuts you down varies by credit card and by your history, but Ulzheimer says, as a general rule of thumb, the spottier your history, the shorter your leash.
"If you have a pretty decent history with the issuer, they may actually allow you to go a whole cycle past due before they shut you down," says Ulzheimer. "If you have a spotty history -- meaning you miss payments all the time -- you'll already be on a short leash, and they won't let you go past one cycle." Customers with a checkered history will need to pay off their past-due amount so they are no longer delinquent.
Missing your credit card payments will hurt you beyond simply having your credit card declined.
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"If you're consistently delinquent, the limit could be lowered," says Nessa Feddis, senior vice president for consumer protection and payments at the American Bankers Association. But again, treatment varies based on each customer's past behavior. "It's not like you'll miss one payment and you're cut off. It has to be sustained delinquency."