rejected 2019 return

2019 E file rejected completed 1040x  (both on turbo tax)  Line 19, 20 and 21a all positive #'s on both the orginal and the amended version.  However, Amended cover sheet Federal Return Summary now reads  "No Refund or Amount Due"  how can that be?  

Thinking it might have been rejected due to QBI and /or carryover issues how can I find out why orginally rejected electronically?