Paying taxes on negative stock year

[donaldtrump]

I just recently amended my tax return, which I already got my full refund for back in like March or late February. I had to amend my return because I needed to add a W-2 for a new job, and include my 1099 forms from trading stocks last year. Long story short, my capital gain last year was -$280 yes that is a negative number. I ended up owing $1900 in federal tax after I included my stock forms. I know the money I owed wasn’t due to the additional W-2 I added because I started the new job December 2020. 
I’m just wondering why I owed almost 2 grand on a negative year of stock trading 

[Hal_Al]

Look at the forms.  What's different between the amended and original?  In particular, look at form 8949 and Schedule D.  Did all that 1099-B inputting get that -$280 on the forms. 

[donaldtrump]

Yes Schedule D shows net gain or loss is -$280. It shows that value on all the related boxes @Hal_Al 

Also I do not see a 1099-B