Reconcile changed previous month ending balance - can't reconcile to current bank statement

Windows 10 Pro
Quicken R45.23 Build 27.1.45.13
Bank-Chase

When processing reconcile to bank statement, I am off. The reconcile window shows the prior month balance not what appears in the bank statement. The prior month reconciled correctly. The amount in Quicken of prior month is the amount I am off in the current month.

I verified each deposit and withdrawal on the bank statement to Quicken; all are verified. I went back to the prior month and did the same cross checking; all are verified.

I use download transactions into quicken and am aware of the Chase download issue. I get all my transaction in the current period with no problem.

I cannot see where the prior month balance has been thrown off.

I the did a Quicken file validation and repair. Worsened the problem. The balance difference went from $54.95 to $544.77 with the same data set. i restored the system from the backup before the validation.

I have 5 years of Chase transactions in Quicken.

What is going on? My wife's Quicke nset for Chase has the same issue on her computer.