The IRS generally requires that you file an amended return on Form 1040X. You may also wish to seek the advice of a licensed tax advisor.
TD Ameritrade must issue a corrected 1099 when mutual funds and Real Estate Investment Trusts (REITs) reallocate or reclassify their distributions in January for the previous tax year. Occasionally this process is not complete, or TD Ameritrade has not yet received the updated information, by the time 1099s are due to be mailed.
IRS regulations require that TD Ameritrade issue a corrected 1099 within 30 days of receiving information showing that the previously issued form was incorrect.