How do I remove a retirement saving contribution credit?

[sfulgham1]

By doing this you are filing an incorrect return.

[dmertz]

Wrong.  Indicating that you are a full-time student in this way has absolutely no effect on your tax return other than to cause Form 8880 to be omitted.  You are not required to claim this credit.  This answer to this question in the Retirement Savings Contributions Credit section of TurboTax is used nowhere else in TurboTax.  For other purposes where TurboTax needs to know if you were a full-time student, TurboTax asks a separate question.