The IRS uses Letter 474C to inform you of changes to your return, usually regarding some credit. Often, it means you owe less tax or will receive a bigger refund.
Response to Letter 474C
This letter should really be in the Math Errors section of this website. But, since taxpayers usually accept it, there's really no need to hire an attorney.
A bookkeeper at TaxHelpReturns may be more beneficial if you have questions. However, if the letter is confusing or states some negative effect on you, please follow the Other Problems Prep Steps. Of course, you may contact Mr. Hopkins for further instructions.