ESPP gain/loss isn't shown correctly in Turbotax compared to what shows in my 1099-B

I uploaded my 1099-B to turbotax installed version. 
Proceeds amount is correctly shown but, Gain/Loss amount isn't matching with my 1099-B. Most of my transactions were ESPP and those are the ones that I made manual changes in.
How can I match this Gain/Loss to 1099-B?