Retirement tax questions

To clarify, is this the worksheet you are entering information on? Also did you check the box above the amount in Box 5 that indicated you are a US Citizen and a resident of Canada? If you checked that Box, it will negate the income because of the US/Canada Treaty Exemption. If you are a US Citizen living in the US, you will not check that box.

Also, the information may have disappeared because this is not taxable income on your return because your SSA income combined with your other taxable income did not reach a income threshold where your social security benefits were taxable.  

Here is the worksheet I was referring to.