The age amount has been transferred to my spouse but is still showing up as a non refundable tax credit on my return

The software calculates how much of the amount you need to reduce your tax liability then transfers the remaining to your spouse. So it is very common to see this amount divided on both returns. 

Please refer to this link for further information on the age amount:

https://turbotax.intuit.ca/tips/claiming-the-age-amount-tax-deduction-5568

I hope this was helpful