I have been having this problem for about 6-12 months (mostly since the method of downloading from banks changed). From multiple banks (Bank of AMerica, Chase, and American Express cards now). Online downloads brings back recent transactions but leaves 'gaps' in prior history.
Today I called customer support (Amy) and s she said this was the bank's decision on changing to a new method and they choose what trx to send?! Sounded really fishy… to me it sounds like a bug. But no - she claims that is bank's decision and we can always go to bank website and download QFX and then upload (yes like I did 5 years ago). Or manually enter transactions (like I did 10 years ago LOL).
So I asked to cancel my subscription renewal. Not sure what the point is of subscription if I'm manually entering data anyways.
Would love to hear from someone else at Quicken if Amy is accurate here.