Why can’t I add my retirement contributions?

What did you contribute to?  If it was at work you only enter it from your W2, nowhere else.  Did you contribute to a IRA outside of work?

I contributed to my 401k and Roth 401k

You have to enter those in the Self-Employed or Business section of TurboTax, where you enter your business expenses. You will see Less Common Business Situations and then an option for Self-employed Retirement.   

But only if it is for your own self employment business.  If you are a W2 employee you only enter 401K from your W2 box 12. Nowhere else.

401K (But not ROTH 401K) come out of your checks pretax and have already been deducted from the wages in box 1 and you can't deduct it again.  See box 1 should be less than boxes 3&5.