After filling 1099-B, the loss is $15,400, however the max loss shown in summary is $2998, not $3k per IRS. Is this a bug calculation or expect i manually fix worksheet?

That does sound unusual.  Was there some other capital gain of $12,000 or so that could have been used as an offset?

Please check your tax return and see what is posted to line 7.

To preview your 1040:

1. On the menu bar on the left that shows.
   1. My Info
   2. Federal
   3. State
   4. Review
   5. File
2. Select Tax Tools
3. On the drop-down select Tools
4. On the popup menu
5. Select View Tax Summary
6. On the left sidebar
7. Select Preview my 1040.

Line 7 - Capital Gain or (Loss)

To return to the entry screens press Back on the sidebar.

If this does not completely answer your question, please contact us again and provide some additional details.