I sold a home for a loss in 2019, Turbo Tax says I do not have to report the sale, the IRS is coming after me as if I sold the home for 100% gain.

[DoninGA]

If you received a Form 1099-S for the sale then it had to be reported on tax return, gain or loss.  The IRS received the 1099-S so now you have to amend the 2019 tax return to include the sale and you will not owe any taxes on the sale of the home.

See this TurboTax support FAQ for amending a 2019 tax return - https://ttlc.intuit.com/community/amending/help/how-do-i-amend-my-turbotax-online-return/01/27577

• Click on Federal Taxes (Personal using Home and Business)
• Click on Wages and Income (Personal Income using Home and Business)
• Click on I'll choose what I work on (if shown)
• Scroll down to Less Common Income
• On Sale of Home (gain or loss), click the start or update button

Or enter sale of home in the Search box located in the upper right of the program screen. Click on Jump to sale of home

[Critter-3]

If a 1099-S was issued at closing then you had to report the sale by clicking on the box that said YES you got a 1099-S ... the closing company should have mentioned this form sometime in the 2 hours you were at their office. 

[DanPaul02]

Selling at a loss does not exclude you from reporting the sale of a home.

You needed to report the sale if:

• It was rental property, or
• It was investment property, or
• You received a 1099-S

Since the IRS is coming after you, it is very likely that you received a 1099-S and did not report it.

You will need to have a copy of the 1099-S.  You will need to determine the basis of the property when you acquired it.  You will need proof of improvements that increased the basis of the property.  You will need all the records of the sale.

if the home was you principal residence for two or more of the five years prior to the sale, then you would qualify for $250,000 exclusion from capital gain for filing single or $500,000 exclusion if married filing jointly.

You will need those records to show that the home was sold at a loss.