How did you download the transactions? Did you use WebConnect? If so, we can try fixing this by excluding the downloaded transactions and re-importing them.
Here's how to exclude:
From the Banking page, go to the For Review tab.
Select the transactions.
Click on Batch actions.
Choose Exclude Selected.
Go to the Exclude tab, and select the transactions.
it happened to me too that I downloaded credit card transactions and for some reason QB chose the wrong credit card account for me. not sure why. anyway, I ended up deleting all the individual transactions from the account. now when I try to reimport them, it tells me 'nothing imported. the account is up to date.' it clearly isn't as the last transactions in that account are from december 2019. also, it switches back to the wrong account, even though I had chosen the correct credit card account prior.