I'm trying to transfer my tuition to my father but it says "Maximum transferable amount is $0.00"?

I have already filed my tax return and it's indicated that I can transfer a set amount of federal tuition to my parent - now when I'm filing my father's taxes and I get to the tuition transfer step, it's stating my "maximum transferable amount is $0.00" after I've entered in all the relevant information from my T1?

Seniors and students

The most common reason for this is an error or omission in the Dependant details. Choose the "Additional Dependant Information" section from the Dependants section of his return. Ensure all of the details about you and your tax return have been entered properly.