I am facing the same exact issue. Its been working fine and since last couple of days QB stopped downloading transactions from Bank of America, but connects fine and no error (Bank of America - New  connection)

Many users complained that yesterday in the forum. But now this morning I tried again to see if the issue is fixed, but now I am getting this error when I tried to download from checking account

"Looks like we didn't find the right type of account to link.

That sign-in info was correct, but we can only connect certain types of accounts. You can try a different bank. (2106)"

I deactivated bank feed and re-activated it again and still the same issue