I entered CPP contributions (box 16) on T4 and EI premiums (box 18) on T4 but they don't show up in my tax summary on line 308 or line 312. Why?

[TurboTaxJennifer]

There could be a couple of reasons for this

1. all of your CPP/EI contributions were overpayments according to your income. Check lines 448/450 for your box 16 & 18 entries.
2. the province of residence has not been entered on the T4 screen. Return to the T4 screen and ensure Box 10 has been selected.