I bought and sold two stocks but each at different brokerages, I couldn't add the stock for the second brokerage. Do I have to upgrade the Deluxe to Premier? Thanks!

Yes, TurboTax will lead you to the upgrade when necessary and stock sales require TurboTax Premium.  

1. Open or continue your return, if you haven't already.
2. Select Search, enter 1099-B, and select Jump to 1099-B.
   1. You can also go to Federal, then Wages & Income, then Investments and Savings.
   2. Select Start or Revisit next to Stocks, Cryptocurrency, Mutual Funds, Bonds, Other (1099-B).
3. Select Okay! on the screen Time to kick off your investments! OR Yes on the screen Did you sell any of these investments? then Continue.
   • If you see Your investments and savings or Your investment sales summary, select Add investments or Add more sales.
   • For more information click this link: Where do I enter my 1099-B?

The Deluxe version worked for 1099-B, I could add more sales. Now the problem is there's no place I can add the second 1099-B from another brokerage. Before upgrading, I want to make sure that the Premier version is capable for adding multiple brokerages than Deluxe version.  Thank you!

Delux and Premium will offer the same service.

At the end of the review of your investments, you would have the option to say yes or no to "any more inestments to report ?"

@yuuhee 

If you are using the Desktop installed program then Deluxe will work.  All the Desktop programs have the same forms you just get more help in Premier for investments.  If you are using the Online web version you need Premium to enter investments.  

@VolvoGirl @fanfare Thanks for the answers. I got it, it's a Turbotax bug. No matter what I did, "add more sales" or "add another sales", Turbotax software always brought me to the same single one brokerage page. I take my laptop offline and reboot, now I can add the second brokerage. No Deluxe-Premier upgrade needed.