I need to understand why I suddenly have Qualified Business Income if I do not own a business.

rental income, 1099 income, REIT, partnership taxes, k-1's are all placed QBI could come from. There is a question during the interview about if it is eligible for QBI. If you received a 1099 DIV with an amount in Box 5 as the dividends from a REIT can be included in the calculation.  Another possibility is if you had any 1099 MISC income with an amount in box 7 (non employee compensation), the IRS requires that income reported on Schedule C and it would be included in the QBI deduction calculation.

It is a REIT. Does not matter that I am not a business?

the REIT is a QBI for 199A and why you are getting it. I hopt this was helpful?

Thanks!  It does not matter that I am not a qualified trade or business or a SSTB?  

The REIT is the qualified business, not you personally