I have been given Investigation #89990, which is a different number than someone listed above, but I have a unique situation that I think could help the engineers looking at this problem. Due to having no full backup (which is supposed to come with my advanced version of QuickBooks), I restored to a backup and lost all history prior to 2023. I was told that the only way to fix the situation was to start a second set of QuickBooks, rebuilt from my backup that I had from my desktop version, and transfer the transactions from my first set of QBO. I have done so and still have both sets of QBO. The first set still syncs with my bank accounts with no issues. When I disconnect the accounts from the first set and try to connect on the old set, it connects one account from each bank and then sometimes syncs with the other accounts, but doesn't keep that connection the next day. Since I have two identical QuickBook accounts with one working correctly, the other not, the engineers might be able to identify the difference between the two and correct the problem. I tried to notify someone at QuickBooks but only get the message that there is no way to communicate with that department!