I have noticed this now a few times with some accounts that the balance is wrong and I notice the Opening Balance (could an account opened years ago) gets set to the most recent transaction value and this screws up the running balance in the entire register. Today it happened on an AMEX account and an FNBO account (yes you can make FNBO work if you set it from Business to Personal - in fact, I had to also do this with my Business Amex accounts!!!) Business CCs don't work correctly lately.
What is going on with Quicken lately and all the weird issues with downloading bank transactions and updating the registers? I'm having to fix / reset / adjust too many accounts lately.