Why would some but not all ALL the 1099-DIVs in last year's return (filed with TurboTax Deluxe 2019 be imported into my 2020 return, being prepared using TurboTax Deluxe?

Is there a limit on the number of 1099-DIVs that will carry forward?  I had imported last year's return, and was entering data from this year's 1099-DIVs into the blank forms that were prepared based on what I had last year, and ended up with two 1099-DIVs (for Intel and Southern Co) that had no blank forms... I though I was going to have to amend last year's return to include dividends... but looking back at last year's return, I found that I had in fact reported the dividends I received from these two companies.  Any idea why blank forms weren't prepared in this year's return?   I look for blank forms to give me a hint that I might have forgotten something, and to have two 1099s randomly omitted is ... disconcerting.