It's not an error. The renewable energy credit and the child tax credit when combined together, can't be greater than your tax liability. However, whenever you are unable to claim the child tax credit because there is no tax liability to offset, you can claim the additional child tax credit, since it is a refundable credit, as long as you have earned income in excess of $3000 and met requirements for the child tax credit. Please refer to the following FAQ to learn more about the child tax credit.
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