If it is a Warning and not an Error, then it can be ignored and skipped. The Warning alert does not automatically mean something was done or entered incorrectly. It can be triggered if a high amount of certain credits or deductions are being claimed. Click on Review to verify that the right amount has been entered by clicking on "Applies to me". Once reviewed you can click "Done with warnings" and return to your review. Warnings are there just to ensure that if the situation applies to you, you can go back and make any necessary modifications.
In this case it is just saying that not all your medical claim will be used as it is higher than what is needed. You don't have to do anything. The amount will just not be allowed in the assessment. For information about your allowable credits please see our TurboTax article: Refundable vs. Non-Refundable Tax Credits: What’s the Difference?
Errors, on the other hand, will prevent you from filing because something in your return is incorrect and the return will not be accepted by the Canada Revenue Agency.
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