How do I show this is the second TIN notice?

Select the checkbox on the 1099 Form for Second TIN Notice.

Use this option when you are notified by the IRS twice within three calendar years that the payee provided an incorrect TIN. Use Government Reporting > 1099 Recipients to look up the account number. Then, click on the tab with the label that corresponds to the form that you wish to void. Then, click to select the 2nd TIN Notice checkbox. When this option is selected, the IRS will not send future notices on this account. However, if you received both IRS notices in the same year, or if you received them in different years but they both related to information returns filed for the same year, do not mark the checkbox at this time.