It's possible that you don't have any tax for the credit to offset, or you may not have paid foreign taxes that qualify for the credit.
You can only claim the credit if you paid, accrued, or owed taxes on foreign income that also was subject to the U.S. income tax system. The tax must have been an income tax, or a tax in lieu of income tax, that was imposed on you, and was a legal foreign tax liability.
Please see the TurboTax Help articles What does or doesn't qualify for the Foreign Tax Credit? and Why doesn't the foreign tax credit show up on Schedule 3, Line 1 of my 1040? for more possibilities on why you may not be receiving the credit.
