From Consumer Wiki
Consumers can call the Federal Trade Commission (FTC) to obtain information on the Federal Fair Credit Billing Act, for billing questions or to file a complaint or to get free information on consumer issues:
To correct a credit card billing error, consumers should follow these basic guidelines:
1. Write to the creditor at the address given for "billing inquiries," not the address for sending payments, and include your name, address, account number and a description of the billing error.
2. Send your letter so that it reaches the creditor within 60 days after the first bill containing the error was mailed to you.
3. Send your letter by certified mail, return receipt requested, so you have proof of what the creditor received, include copies (not originals) of sales slips or other documents that support your position. Keep a copy of your dispute letter.
Federal Trade Commission
Bureau of Consumer Protection
Division of Consumer and Business Education
600 Pennsylvania Avenue, Northwest
Washington, D. C. 20580
See also: Federal Trade Commission, Fair Credit Reporting Act
Other referrals: Federal Fair Credit Billing Act, 15 U.S.C. Sections 1666 and 1666I, and Federal Reserve Regulation Z, 12 CFR sections 226.12(c) and 226.13. The California law is the Song-Beverly Credit Card Act, Civil Code sections 1747, et seq.