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Those pieces of information have saved me a lot of trouble on several occasions!

I always dial my husband's mobile number by hand, and usually my close friends and family's numbers, too.

Credit card: I try entering the number, expiration and check digits from memory, then check it against the card before submitting the order. When the card number changes (bank decision or mine), I learn the new one by learning the differences - the first four digits are almost always the same, as that's a bank identifier. With AmEx, the variance was only in the last five digits, and was slight.



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