We are aware of this issue, and our development team is working on a resolution. Currently we don't have any ETA. Once it is resolved, we will update you in this thread. We appreciate your patience.

Thank you for choosing TurboTax.

Any update of resolution?

@suliang 

Do you have any amounts in Box 52 or Box 53? If you only have an amount in Box 21, you need to enter the amount in Box 52 or Box 53 for it to go the Schedule 3.

This does not work for me, I entered corresponding data box 21 and 53 and schedule 3 still does not populate. 

what is worse I assume capitals gains will be taxed at 100% and furthermore I cannot claim my net capital loss carry forward. 

I really cannot believe this. I will not use this software again, such a basic issue.